. To __ terrorism, what action should be taken?

My new neighbor is a _____ person; he never speaks to anyone and nobody knows where he is from and what he is doing.

I came across myold friend,Bob,this afternoon.He gave me a cold look though.It looked as if I________a stranger to him.[ ]

Plastic parts can ______ metal ones in many machines.But they don’t last long.

It seems that your cousin Mary is talking with her daughter over there. —I don’t think so. It _____ be her because she called me from her home just now.