You’d better take an umbrella when you go out, because it ________rain.
句意：当你出门时，最好带一把伞，因为可能会下雨。
考查情态动词辨析。must一定；should应该；might可能；need需要。根据“You’d better take anumbrella when you go out, because it...rain.”可知此处表示可能性较小的推测，推测会下雨。故选C。
You’d better take an umbrella when you go out, because it ________rain.
The man _______ be a doctor in this hospital, but I’m not sure.
—Whose notebook is this?
—It ________ be Alan’s. It looks like his.
Mary ________ go to London next year but she is not sure.
