Mike must have known that.—No, he ________. How _______ he?

No one had told Smith about __________ a lecture the following day．

These teenagers don’t know much of the world yet; that’s why they are so easily _____. [ ]

Ican’t leave She told me that I stayhere until she comes back

so many people at the party, I _______ John, one of my classmates after 20 years.