20．Why is he not allowed to stay here?　　　　 , it’s his home.

　　　 A．In all　　　　　　　　　 B．After all　　　　　　 C．In other words D．To be frank

19．She is a diligent student, and all her spare time she has　　　 staying in the library.

　　　 A．is spent 　　　　　　 B．spent　　　　　　　　 C．to spend　　　　　 D．to be spent

18．I still remember how many years ago 　　　　　I last met her in the countryside.

　　　 A．when it was　　 B．was it that　　　　 C．when was it 　 D．it was that