In English conditional tenses are used for speculation. We can speculate about what could happen, what might have happened, and what we wish would happen. In English, most sentences using the conditional contain the word if. The unreal past is when we use a past tense but we are not talking about something that really happened.
A type 2 conditional is used to refer to a time that is at any point in time, and a situation that is unreal or unlikely. These sentences are hypothetical. The type 2 conditional is used to refer to a hypothetical condition and its probable result. In type 2 conditional sentences, the if clause uses the simple past, and the main clause uses the present conditional.
Example: If I were a rich man, I would have a big house.
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