20．-----Are you sure Nick will help us if we are in trouble?

----　　　　 He is a reliable friend.

A．It doesn’t matter　　　　 　　　 B．Don’t take it to heart.

C．You can count on it　　　 D．No problem.

19．---Did you visit the National Stadium last week?

----I should have ,but an old friend of mine　　　

A．drops in　　　　　 B．dropped in　　　　 C．had dropped in　 D．has dropped in

18．It’s said that an American starts a speech with a joke ,　　　 a Japanese seldom.

A．as　　 　　　　　　　　　　　 B．when　　　　 　　　 C．though　　　 　 D．while