The processor controls all of the ... of a computer.

A. activities

B. activity

C. actively

D. active

He was really ... about the fairwell party last night.

A. excite

B. exciting

C. excitingly

D. excited

You must remember to recharge your phone. Without its batteries, it's ... .

A. useful

B. useless

C. usefully

D. uselessly

The organization focuses more ... educating disadvataged children.

A. on

B. at

C. in

D. to

It is important to contact ... other teenagers with similar interests.

A. of

B. out

C. in

D. with