In a type 1 conditional sentence, the tense in the "if" clause is the simple present, and the tense in the main clause is the simple future.
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We use the type 1 conditional
to refers to a possible condition and its probable result.
These sentences are based on facts, and they are used to make statements about the real world, and about particular situations. We often use such sentences to give warnings. In type 1 conditional sentences, the time is the present or future and the situation is real.
If I have time, I'll finish that letter.
What will you do if you miss the plane?
Nobody will notice if you make a mistake.
In type 1 conditional sentences, you can also use modals in the main clause instead of the future tense to express the degree of certainty, permission, or a recommendation about the outcome.
If you drop that glass, it might break.
I may finish that letter if I have time.