Choose the modal for possibility: "It rain after school today."
- must
- can
- might (correct answer)
- should
Explanation: "Might" is the best choice because it shows something is possible but not sure, which fits a guess about the weather. "Must" tells us something is almost certain to happen, and we cannot be that sure about rain. "Can" tells us something is able to happen in general, not that it is likely today. "Should" tells us what we expect or what is a good idea, not that rain is simply possible.