A simple sentence has just one clause. Examples are given below.
He went to the market.
She recognized them at once.
I have paid the fee.
A compound sentence has two or more coordinate clauses connected by a coordinating conjunction. Examples of such connecting expressions are: and, but, or, for, so, yet, either…or, neither…nor, both…and
We can convert a simple sentence into a compound sentence by expanding a word or phrase into a coordinate clause.
Study the examples given below.
She came here to see me. (Simple)
She came here and saw me. (Compound sentence)
Here we expanded the infinitive to see into a coordinate clause.
In spite of his hard work, the boy didn’t succeed. (Simple sentence)
The boy worked hard, but he didn’t succeed. (Compound sentence)
Here we expanded the prepositional phrase ‘in spite of his hard work’ into a coordinate clause.
The teacher praised the boy for his diligence. (Simple sentence)
The boy was diligent, so the teacher praised him. (Compound sentence)
Having finished their work for the day, the masons went home. (Simple sentence)
The masons finished their work for the day and went home. (Compound sentence)
In spite of his popularity, he cannot be considered as a great writer. (Simple sentence)
He is popular but he cannot be considered as a great writer. (Compound sentence)