Conditionals

Conditional tenses are used to 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. Many conditional forms in English are used in sentences that include verbs in one of the past tenses. This usage is referred to as "the unreal past" because we use a past tense but we are not actually referring to something that happened in the past.

There are five main ways of constructing conditional sentences in English. In all cases, these sentences are made up of an if clause and a main clause. In many negative conditional sentences, there is an equivalent sentence construction using "unless" instead of "if".

Conditional Clause and Main Clause

-If I have enough money,	I will go to Japan.
conditional clause	main clause

-I will go to Japan,	If I have enough money.
main clause	conditional clause

Conditional sentence type	Usage	If clause verb tense	Main clause verb tense
Zero Conditional	General truths	Simple present	Simple present
First Conditional	A possible condition and its probable result	Simple present	Simple future
Second Conditional	A hypothetical condition and its probable result	Simple past	Present conditional or Present continuous conditional
Third Conditional	An unreal past condition and its probable result in the past	Past perfect	Perfect conditional
Mixed Conditional	An unreal past condition and its probable result in the present	Past perfect	Present conditional

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