Talking about a Likely Future Event

Maybe you already know about the "first conditional." The first conditional is a structure we use in English to talk about a likely future event.

For example:

If I get a good grade on the test, I will have a party.

In this example, we use the present simple tense to describe the condition, or the probable future event. We use the future tense with will + base verb to talk about the result. The result is what happens if the condition does happen in the future.

So, this example sentence means "I believe that I probably get a good grade on the test. I will have a party if I do."

But did you know that you can also sometimes use modals like might, must, can, shall, or may instead of will?

If I get a good grade on the test, I might  have a party. -
(It's possible I will have a party if I get a good grade on the test.)
If I get a good grade on the test, I must have a party. -
(I have had poor grades in the class this semester so far. I think I can pass this test. I feel like it is necessary that I celebrate if I do!)
If I get a good grade on the test, I can have a party.-
(My parents gave permission for me to have a party if I get a good grade on the test.)
If I get a good grade on the test, I shall  have a party.-
(like "I will")
If I get a good grade on the test, I may have a party.-
(It is possible that I will have a party if I get a good grade on the test.)

You can also switch the condition and result parts of the sentence.
I will have a party if I get a good grade on the test.
I might have a party if I get a good grade on the test.
I must have a party if I get a good grade on the test.
I shall have a party if I get a good grade on the test.
I may have a party if I get a good grade on the test.
I can have a party if I get a good grade on the test.