The document describes four types of conditional sentences in English. Type 1 conditional sentences describe what always or usually happens using "if" and simple present tense. Type 2 conditional sentences describe possible future situations using "if" and "will". Type 3 conditional sentences imagine different present situations using "if" and "would". Type 4 conditional sentences describe imagined past situations that didn't happen using "if" and "would have". Examples are provided for each type.

1. •Zero Conditional
•Conditional type 1
•Conditional type 2
•Conditional type 3

2. These sentences describe what always or
usually happens or give instruction.
 If I have a cold, I stay at home.
 If you feel tired, have a rest.
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4.  These sentences describe possible situations
and their results. They may also be a warning.
 If we miss the bus, we will be late.
 If you ride your bike like that, you will fall
off!
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6.  These sentences imagine a different present
time, they are imaginary situations. We can
also use them to give advice.
 If I knew the answer, I would tell you.
 If I were you, I would take an aspirin.
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8.  These sentences are used to describe a
situation that didn’t happen, and to imagine
the result of this situation.
 If I had studied, I would have passed the test.
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