Simple, Compound, and Complex -Best 7 Powerful Rules

Transforming sentences from one form to another—Simple, Compound, and Complex—is a vital skill in English grammar. It helps express the same idea in different sentence structures, enhancing writing and speaking fluency.

In this lesson, you’ll master sentence transformation techniques with rules, structures, and practical examples.

Read more – Completing Sentence: Top 20 Powerful Rules with Easy Examples

Sentence Types Overview

Type	Definition
Simple	A sentence with one independent clause.
Compound	A sentence with two independent clauses joined by coordinating conjunctions.
Complex	A sentence with one independent clause and one or more dependent clauses.

Sentence Transformation Rules: At a Glance (Simple ⇄ Compound ⇄ Complex)

Transformation Type	Simple	Compound	Complex
1. In spite of / Despite	In spite of + possessive noun/pronoun + verb + ing	Subject + verb + but + subject + verb	Though / Although + subject + verb
2. Without / Unless / If Not	Without + verb + ing	Verb + or + subject + verb	If + subject + do/does not + verb
3. By + Verb-ing / When	By + verb + ing	Subject + verb + and + subject + verb	When + subject + verb
4. Too…to / So…that	Subject + verb + too + adjective + to + verb	Subject + verb + and + subject + cannot + verb	Subject + verb + so + adjective + that + subject + cannot + verb
5. Because of / As / Since	Because of + noun/possessive + verb-ing	Subject + verb + and + subject + verb	As / Since / Because + subject + verb
6. Infinitive “To”	Subject + verb + to + verb	Subject + verb + and + subject + verb	Subject + verb + so that + subject + can/could/might + verb
7. Participle (V-ing or V3)	Verb-ing / V3 + rest of sentence	Subject + verb + and + subject + verb	When + subject + verb

Clause to Phrase Conversions

Complex (Clause)	Simple (Phrase)
When I was five, I went to school.	At the age of five, I went to school.
It is he who is a good student.	He is a good student.
I saw a man who was blind.	I saw a blind man.
I do not know where he lives.	I do not know his address.

Transformation Rules and Structures

1. In spite of / Despite

• Simple: In spite of + possessive noun/pronoun + verb + ing
• Compound: Subject + verb + but + subject + verb
• Complex: Though / Although + subject + verb

🔹 Example:

• Though he was poor, he was honest. (Complex)
  → He was poor but honest. (Compound)
  → In spite of his being poor, he was honest. (Simple)

2. Without / Unless / If Not

• Simple: Without + verb + ing
• Compound: Verb + or + subject + verb
• Complex: If + subject + do/does not + verb

🔹 Example:

• Without reading, you will not pass. (Simple)
  → Read or you will not pass. (Compound)
  → If you do not read, you will not pass. (Complex)

3. By + Verb-ing / When

• Simple: By + verb + ing
• Compound: Subject + verb + and + subject + verb
• Complex: When + subject + verb

🔹 Example:

• By reading regularly, you will learn. (Simple)
  → Read regularly and you will learn. (Compound)
  → If you read regularly, you will learn. (Complex)

4. Too…to / So…that

• Simple: Subject + verb + too + adjective + to + verb
• Compound: Subject + verb + and + subject + cannot + verb
• Complex: Subject + verb + so + adjective + that + subject + cannot + verb

🔹 Example:

• He is too weak to walk. (Simple)
  → He is very weak and cannot walk. (Compound)
  → He is so weak that he cannot walk. (Complex)

5. Because of / So that / As / Since

• Simple: Because of + noun/possessive + verb-ing
• Compound: Subject + verb + and + subject + verb
• Complex: As / Since / Because + subject + verb

🔹 Example:

• Because of his laziness, he failed. (Simple)
  → He was lazy and failed. (Compound)
  → As he was lazy, he failed. (Complex)

6. Infinitive “To”

• Simple: Subject + verb + to + verb
• Compound: Subject + verb + and + subject + verb
• Complex: Subject + verb + so that + subject + can/could/may/might + verb

🔹 Example:

• He worked hard to succeed. (Simple)
  → He worked hard and succeeded. (Compound)
  → He worked hard so that he might succeed. (Complex)

7. Participle Structure (V-ing or V3)

• Simple: Verb-ing + rest of the sentence
• Compound: Subject + verb + and + subject + verb
• Complex: When + subject + verb

🔹 Example:

• Closing the door, he left. (Simple)
  → He closed the door and left. (Compound)
  → When he closed the door, he left. (Complex)

Read more – Mastering Conjunctions: 3 Types, Powerful Uses & Examples

Example Sentences for Practice

1. He worked hard but failed.
   → Complex: Though he worked hard, he failed.
   → Simple: In spite of working hard, he failed.
2. Move or you will die.
   → Complex: If you do not move, you will die.
   → Simple: Without moving, you will die.
3. He walked fast to catch the train.
   → Complex: He walked fast so that he could catch the train.
   → Compound: He walked fast and caught the train.
4. He is rich but unhappy.
   → Complex: Although he is rich, he is unhappy.
   → Simple: In spite of being rich, he is unhappy.
5. Rubel went to the market and bought a pen.
   → Complex: When Rubel went to the market, he bought a pen.
   → Simple: Going to the market, Rubel bought a pen.

Clause to Phrase Conversion

Complex (Clause)	Simple (Phrase)
When I was five, I went to school.	At the age of five, I went to school.
It is he who is a good student.	He is a good student.
I saw a man who was blind.	I saw a blind man.
I do not know where he lives.	I do not know his address.

Do Yourself

Change the following sentences into Simple:

1. If you watch television, you can learn many things. (Make simple sentence)
2. As the demand for flowers is increasing day by day, we should cultivate flowers on commercial basis (Simple)
3. When he was a boy, he desired to be an Englishman. (Make it a simple sentence)
4. He went to Europe and started composing poems. (Make it a simple sentence)
5. One night when he was saying his prayer, a thief broke into his room. (Make it a simple sentence)
6. The people who are poor cannot afford to take a balanced diet. (Make simple sentence)
7. When I reached there, my friend received me cordially. (Simple)
8. If a student fails in the examination, he suffers from inferiority complex. (Make simple sentence)
9. So a student should be aware of studying regularly and attentively so that he can do well in the examination. (simple)
10. One night when he was saying his prayer, a thief broke into his room. (Simple)
11. There he came in contact with many people and learnt many things about them. (Simple)
12. Gold is a metal which is very precious. (Simple)
13. They fade soon and lose their beauty. (Simple)
14. So, a student should be serious to study if he wants to enjoy a better life. (Simple)
15. The roast looked so delicious that the cook could not check his temptation to eat up one of the drumsticks. (Simple)
16. The cook insisted that his duck had only one leg. (Simple)
17. Then the cook saw some ducks which were resting outside in the courtyard. (Simple)
18. It put down its leg and ran off. (Simple)                                                                                                                                                                                                                           
19. When a man makes a journey by train he can enjoy natural scenery. (Simple)
20. He entered the kingdom of a prince and captured a large village. (Make it simple)
21. He disguised himself as a poor traveller and supported himself by begging. (Make it simple)
22. Taimur was so hungry that he did not wait. (Make it simple)
23. If we read books we can discover new worlds. (Simple)
24. If we do not read books, we cannot keep pace with modern life. (Simple)
25. He who is taken by anger causes a lot of troubles. (Simple)
26. He put on an ordinary dress and set out for the emperor’s palace. (Simple)
27. The courtier received him cordially and entertained him with rich and delicious foods. (Simple)
28. When we start practising truthfulness, there arise some problems. (Simple)
29. Bangladesh is a small country but has a huge population. (Simple)
30. If you watch television, you can learn many things. (Simple)
31. There is no living being that does not need pure air. (Simple)
32. She consulted her courtiers and decided to see the wise Solomon. (Make it simple)
33. She gazed at this writing again and again and thought over it. (Make it simple)
34. She put the garlands in front of Solomon and asked him to select the natural one. (Make it simple)
35. They came in and settled on the garland made of natural flowers. (Make it simple)
36. The man who takes bribe is next to devil. (Simple)
37. One night when he was saying his prayer, a thief broke into his room. (Make simple sentence)
38. Newspaper is a paper that contains news of home and abroad. (Simple sentence)
39. Many visitors buy books from this fair as they like. (Simple)
40. As the paws are cushioned, a big tiger can walk through the driest leaves without causing a single crackle. (Simple)
41. They are not only strong but also ferocious. (Simple sentence)
42. When they walk, they don’t make any sound. (Simple)
43. But education covers development of mind and taste which is done through study. (Simple)
44. If we do not cultivate the habit of speaking the truth, we cannot command the confidence of others. (Simple)
45. But it is man who is the maker of his own fortune. (Simple)
46. If they are educated, they can be skilled. (Simple)
47. They raise the price and get more benefits. (Simple)
48. Though computer is a blessing, it has some dark sides. (Simple)
49. We must educate all if we want to get a better future (Make simple sentence)
50. Those who are criminals also use this device. (Simple)
51. He is a good boy and he will be rewarded. (Simple)
52. Sami cannot go unless I permit. (Make simple sentence)
53. It ennobles one’s character and gives one high position in society. (Make it simple)
54. Those who live in Dhaka fall victim to pollution. (Simple)
55. Those who are honest lead a happy life. (Simple)
56. If you take care of your health, you can enjoy a good life. (Simple)
57. If he makes a proper use of his time, he is sure to prosper in life. (Simple)
58. If he does otherwise, he is sure to repent. (Simple)
59. In youth the mind is soft and can be shaped in any form you like. (Simple)
60. One can go a long way if one does anything with sincerity. (Make it simple)

Read more – Simple, Compound and Complex Sentences Exercises

Change the following sentences into Complex:

1. We need flowers to decorate a place. (Complex)
2. Scientists spent many years to invent television. (Make complex sentence)
3. The programmes telecast by television are very interesting. (Make complex sentence)
4. He was born at Sagordary on the bank of the Kapotaksho. (Make it a complex sentence)
5. He was born in Hoogly. (Make it a complex sentence)
6. He caught the thief but did not punish him. (Make it a complex sentence)
7. Health is wealth. (Make complex sentence)
8. He can succeed in life. (Make compound sentence)
9. My friend invited me to pay a visit to Cox’s Bazar. (Complex)
10. The students studying regularly can expect a good result. (Make it a complex sentence)
11. By repeating this activity they make a poor result. (Make it a complex sentence)
12. During his lifetime, he spent money lavishly to help the poor. (Complex)
13. He became a sailor in his boyhood. (Complex)
14. During his voyage on the Mediterranean, he went to many parts of Europe and Africa. (Complex)
15. People in general are fond of glittering things. (Complex)
16. The students studying seriously can expect to make an excellent result; (Complex)                                                                                                   
17. He threatened to fire the cook from his job. (Complex)
18. There are class distinctions in a train and people can buy tickets of various classes. (Complex)
19. Taimur’s soldiers were all killed but Taimur escaped with great difficulty. (Make it complex)
20. He came to a house and asked an old woman to give him something to eat. (Make it complex)
21. She felt pity for him and quickly gave Taimur a full, I dish of food. (Make it complex)
22. While reading books we enter into a new world sabi (Complex)
23. Such a vice destroys. humanity in man. (Complex)
24. On the way, he took shelter in a courtier’s house. (Complex)
25. On his way back home, Saadi again took shelter in the same courtier’s house. (Complex)
26. The courtier’s men were surprised to see Saadi’s putting his foods in the pockets of his dress. (Complex)
27. Some people think that the practice of truthfulness is difficult but their idea is wrong. (Complex)
28. We need more educational institutions to provide for the increasing number of students. (Complex)
29. Fresh air is necessary for our existence. (Complex)
30. So we should be aware to prevent air pollution. (Complex)
31. Scientists spend many years to invent television. (Complex)
32. Television    telecasts    interesting programmes. (Complex)
33. It started with the name of Allah, the Beneficent and Merciful. (Make it complex)
34. He looked around and saw some bees humming outside on the withered roses. (Make it complex)
35. She made peace with Solomon and got married to him. (Make it complex)
36. A corrupted man can do anything against morality. (Complex)
37. He was bom in Hoogly. (Make complex sentence)
38. During his life time, he spent money lavishly to help the poor. (Make complex sentence)
39. He caught the thief but didn’t punish. (Make complex sentence)
40. People read newspaper to know various things. (Complex sentence)
41. We should read books to enrich our minds. (Complex)
42. Every year a book fair is held at Ramana Batamul in Dhaka. (Complex)
43. Tigers are known as ferocious animals. (Complex)
44. Most of our people cannot read and write.
45. Literacy is the ability to read and write. (Complex)
46. This virtue makes a man really great. (Complex)
47. By earning money, he/she can be self-sufficient. (Complex)
48. People lead a miserable life. (Complex)
49. There is no unmixed blessing on earth. (Complex)
50. It is too poor to imagine. (Make complex sentence)
51. We must remove illiteracy to develop our country. (Make complex sentence)
52. As we are illiterate, we can’t progress. (Make compound sentence)
53. We use mobile phone to make rapid communications. (Complex)
54. I did this and so offended him. (Make complex sentence)
55. A studious boy can shine in life. (Complex)
56. It may not make one rich but it brings peace in mind-(Make complex)
57. Dhaka stands on  the famous Buriganga river. (Complex)
58. In spite of taking utmost care, we cannot avoid indiscipline. (Complex)
59. Our life is nothing but the sum total of hours, days and years. (Complex)
60. Youth is the golden season of life. (Complex)
61. Sincerity re the root of success in all work. (Make it complex)

Change the following sentences into Compound:

1. Without reading carefully, you will not pass in the examination. (Make compound sentence)
2. People spend their free time by watching television. (Make compound sentence)
3. Due to the flowers having sweet scent and beauty we love it very much. (Compound)
4. During his lifetime he spent money lavishly to help the poor. (Make it a compound sentence)
5. He was so kind that he could not refuse anyone’s request. (Make it a compound sentence)
6. Though a healthy man is an asset to his family, an unhealthy man is a liability. (compound)
7. Every year a lot of people come to visit it. (Compound)
8. Seeing Muhsin the thief cried. (Compound)
9. During these voyages very often Columbus gazed at the vast sheet of unlimited water. (Compound)
10. But there are some other metals looking like gold. (Compound)
11. By doing this they make poor result. (Compound)
12. When his master sat down to eat, he quickly noticed the missing leg. (Compound)
13. He drew the attention of his master to show him this. (Compound)
14. People like it as it is cheap. (Compound)
15. When the news reached the prince, he came with a large army. (Make it compound)
16. Realizing it we should try to be emotionally balanced. (Compound)
17. Seeing him in an ordinary dress, the courtier and his men did not show much honour and hospitality to him. (Compound)
18. They cannot educate their children for poverty. (Compound)
19. People spend their free time watching television. (Compound)
20. Though we have strict law, we are still affected by this evil. (Compound)
21. He was so kind that he could not refuse any one’s request. (Make compound sentence)
22. We should read newspaper to enrich our knowledge. (Compound sentence)
23. If we do not read book, we cannot keep pace with the advanced world. (Compound)
24. They hunt after they target their prey. (Compound)
25. Literacy is so important that it is called the platform of education. (Compound)
26. Many do not try to better their condition by hard labour. (Compound)
27. The greedy people are responsible for it. (Compound)
28. It renders mankind a service which is great. (Compound)
29. Though it is very useful, it has some demerits. (Compound)
30. Despite congestion, Dhaka has a rich heritage. (Compound)
31. If we lose the morning hours of life, we shall have to repent after wards. (Compound)