1 . —How do you learn English, Tony?
—I often practice English _____ chatting ______ my American friends.

A．in; with

B．by; of

C．by; with

D．by; from

2 . ——_____do you tell him about the event? ——By ____e-mail.

A．How；send.	B．How；sending
C．What ；sending	D．What ；send

3 . —How did you work out the difficult chemistry problem?
—I worked it out by ________.

A．working with a group	B．think very hard
C．ask the teacher for help	D．doing oneself