—Must I buy lunch at school?—No, you needn’t. You __________ bring your own lunch if you want to.

Liza ______ well want to go on the trip ― she likes traveling.

As we all know, it is usually cold in this place in January, but it _____ be warm sometimes.

--Pauline has lost her phone.  –No. It’s in her bag. I _________ hear it.

Since nobody gave him any help，he ________ have done the research on his own.