1 . Scientists are convinced _____ the positive effect of laughter _____ physical and mental health.

A．of; at	B．by; in
C．of; on	D．on; at

2 . Sometimes proper answers are not far to seek ________ food safety problems.

A．in	B．to
C．on	D．after

3 . When asked about their opinion about the schoolmaster ,many teachers would prefer to see him step aside __________ younger men.

A．in terms of

B．in need of

C．in favor of

D．in praise of

4 . Children need friends ______ their own age to play with.

A．of

B．for

C．in

D．at

5 . Most Americans would prefer to keep their problems ______   themselves, and solve their problems ______ themselves.

A．to; by

B．by; to

C．for; to

D．in; on

6 . This special school accepts all disabled students, ______ educational level and background.

A．according to	B．regardless of
C．in addition to	D．in terms of

7 . It saves time in the kitchen to have things you use a lot _______ easy reach.

A．near	B．upon
C．within	D．around