20．－Did you enjoy yourself last night?

　　　 －Yes, it’s very nice of you．I appreciated　 　　　to the party.

A．to be invited 　　　　　　　　　　　　　　　　　　　 B．to have invited

C．having been invited　 　　　　　　　　　　　　 D．being invited

19．－Hello, Anne, it’s Jack here. Can I speak to Robert, please?

　 　 －Hi, Jack. Robert　　 　in the garage. Can I get him to call you back?

　 　 －Sure. Thanks.

　　 A．has worked　 　　 B．is working　　 　　 C．worked　　　 　　 D will work