Conditional sentences. “If” clause: verb in present, main clause: verb in past

The other component of a conditional sentence is the main clause, which can also be referred to as unreal, or imaginative and contrary-to-fact. A conditional sentence that begins with an “if” clause in the present and ends with the main clause in the past express events that impossible and unlikely to happen in the future, or did not happen in the past. Teachers may also refer to these sentences as present or future unreal conditional sentences. In unreal conditional sentences, the past tense in the “if” clause refers to a present or future event. Therefore, the form of the conditional sentence is as follows:

If + simple past, would + verb

Consider the following sentence:

If I had time, I would clean the house.

The speaker in this sentence is advising the listener they do not have time to clean the house.