______ Tom______ Mary speaks good Chinese, so they communicate with these Chinese students very well.

Susan’s parents have bought a large house with a swimming-pool. It ____ be very expensive.

This cake is different _____ that one.[ ]

Do you know the activity called “________ Lights” ?—Oh,it’s an activity that reminds people of saving energy.

The socks are cheap（便宜的）， I’ll________ it.