15. Look at this sign. What does it mean?

A.        Dropping litter is forbidden.

B.        Empty the garbage.

C.        Put the rubbish into the bin.

D.        No littering.

16. Look at this sign. What do you think about it?

A.        I allow myself to make noise.

B.        I should keep quiet.

C.        I shouldn’t point my finger to the nose.

D.        I can talk as much as possible.