How long have you ______ ?

—I haven’t seen my close friend John lately,and I wonder how things go with him?—I _____him the other day,he said he worked in a candy store.

You’d better have your bike ________, or it’ll get you into trouble.

When I came into the teacher’s office, he ________ on the phone.

Experts say walking is one of the best ways for a person to _______ healthy.