Conditional sentences
What is conditional sentences?
A conditional sentence expresses a hypothetical situation, where one action or event depends on another. It usually consists of two clauses: the if clause (the conditional clause) and the result clause (the main clause).
Based on the likelihood of the condition being fulfilled, conditional sentences are divided into 4 main types:
The Zero Conditional
This type of conditional is used to talk about general truths or scientific facts. It describes a situation where the condition and result are both true in the present. The tense used in both clauses is the present simple.
If you heat water, it boils.
The First Conditional
This type of conditional is used to describe a situation that is likely to happen in the future. It describes a real and specific condition and its possible result.
The tense used in the conditional clause is the present simple, and the tense used in the result clause is the future simple or the imperative.
If it rains, I will stay at home.
If your colleague is absent, you have to do their works.
The Second Conditional
This type of conditional is used to describe an imaginary or unlikely situation in the present or future. It describes a condition that is unlikely to be fulfilled and its result, which is usually imaginary or hypothetical.
The tense used in the conditional clause is the past simple, and the tense used in the result clause is the conditional (would + base form of the verb).
If I had a million dollars, I would buy a house.
The Third Conditional
This type of conditional is used to describe a hypothetical situation in the past. It describes a condition that was not fulfilled and its imaginary result, which would have happened if the condition had been fulfilled.
The tense used in the conditional clause is the past perfect, and the tense used in the result clause is the conditional perfect (would + have + past participle).
If I had studied harder, I would have passed the exam.
We can express the third conditional in more formal or literary contexts by moving had to the beginning of the sentence and remove if:
Had I studied harder, I would have passed the exam.