Question

Combine two simple sentences below to form a simple sentence:
They must practice hard. They will win.
A) If they practice hard, they will win
B) They must practice hard and they will win
C) Unless they practice hard, they cannot win
D) They must practice hard to win

Answer 1

Hint: Sentences that contain a single subject and single predicate are called simple sentences. Simple sentences have independent clauses.

Complete answer:
 Option A: If they practice hard, they will win
In this option they will win the independent sentence but the other part of a sentence if they practice hard do not make complete sentences they are dependent on other sentences to make meaningful sentences. It is a subordinate clause.
This is not a simple sentence so it is not the correct option.
Option B: They must practice hard and they will win
In this option, they must practice hard to make good sense and they will win also make good sense but in this sentence, there are two subjects in two sentences. Hence this is a compound sentence. This is not a simple sentence so it is not a correct option.
Option C: Unless they practice hard, they cannot win.
In this option ' they cannot win' independent sentences but the other part of the sentence unless they practice hard does not make a complete sentence they are dependent on another sentence to make meaningful sentences. Unless is a subordinate clause.
This is not a simple sentence so it is not the correct option.
Option D: They must practice hard to win
This is an independent sentence with a single subject(they) and predicate. Hence it is a simple sentence. So the correct answer is option is (D).

Note:
There are two types of sentences: simple and compound sentences. A simple sentence has an independent sentence. A compound sentence has one dependent clause and the other is an independent sentence that makes complete sense. It has more than one subject.