Compound to Complex

When two clauses are joined by AND, BUT or, OR, we call it compound sentence. To make it complex, we use a sub-ordinate conjunction and make one clause depended on other. 

1. Two clauses of opposite ideas joined with but form compound sentence. To make it complex, we make the first clause an adverbial clause of concession. That is, we put though/ although before the first clause. If the sub-ordinate clause of concession is put first, we put a comma between the two clauses. If the sub-ordinate clause is put after the main clause, we don’t put any comma.


Compound: He is poor but happy. 

Complex: Though he is poor, he is happy. 


Compound: A truthful person may lead a poor life but is honored everywhere.

Complex: Although a truthful person may lead a poor life, he is honored everywhere.


1. Transform the following compound sentences into complex. 

(a) He also tried his best to make them accept the truth but both clung to their claims. 

(b) Life of a man is not very peaceful but honesty can open a door of peace before him. 

(c) He also tried his best to make them accept the truth but both clung to their claims. 

(d) One woman remained quiet but the other one cried out in sorrow.

(e) Bangladesh is a small country but has a huge population.


2. Two clauses of alternative ideas joined with or form compound sentence. To make it complex, we make the first clause an adverbial clause of negative condition. That is, we put if (not)/ unless before the first clause. If the sub-ordinate clause of condition is put first, we put a comma between the two clauses. If the sub-ordinate clause is put after the main clause, we don’t put any comma.


Compound: Help me or I will fail.

Complex: If you do not help me, I will fail.


Compound: Pay the bill timely or they will fine you.

Complex: If you do not pay the bill timely, they will fine you.


2. Transform the following compound sentences into complex. 

(a) Do or die.

(b) Move or die.

(c) Speak to me more politely or I will kill you. 

(d) You must hurry or you will miss the train.

(e) They should be more sincere or they will miss the chance. 


3. If two clauses joined with and form a compound sentence, we make it complex with the help of the following sub-ordinate conjunctions.

Sub-ordinate Conjunction
When to Use
As/ since/ because
When one clause indicates reason
When
When one clause indicates time
Where
When one clause indicates place
Why
When one clause indicates reason
Who/ which/ that
When one clause modifies the noun or pronoun of the other clause.

Compound: An ant was thirsty and wanted to drink.

Complex: An ant which was thirsty wanted to drink.


Compound: It was twenty years ago and I was living in Paris.

Complex: It was twenty years ago when I was living in Paris.


Compound: They are lazy and don't make their own nests.

Complex: They don't make their own nests because they are lazy.


3. Transform the following compound sentences into complex. 

(a) The demand for flowers is increasing day by day and so we should cultivate flower on commercial basis.

(b) Our students cultivate the good qualities in character and they will certainly lead the nation.

(c) Suddenly they saw a bear and it was coming towards them.

(d) The people are poor and cannot afford to take a balanced diet.

(e) Gold is a metal and it is very precious.

(f) It is a telephone system and it works without any wire.

(g) We read good books and discover new worlds.

(h) He was eight years old and then his mother died.

(i) The plane had taken off and a hostess came to me.

(j) Move and you will die.