Who is ________, Tom, Mike or Jim— I think Jim is.

Teterboro is the same airport ____a planetook off earlier this morning before colliding (碰撞)with a sightseeing helicopter over the HudsonRiver.

Jack, you look so tired!—Well, I _____the house and I must finish the work tomorrow.

Mary is very clever and _____ worth teaching, but her brother is not Look, he is now _____ asleep in class

One of the most important things in education is to let students ____ positive emotions and experience in the process of their learning.