Did you enjoy yourself last night—Yes, it’s very nice of you. I appreciated to the party.

Doctor Smith has made another wonderful discovery, _______ great importance.

Have you really been to visit the Bird’s Nest in Beijing?　 —- I ______ it last summer vacation.

our earth, or else it will be no longer fit for us to live on.

He stopped his ears with his hands to _____ the terrible noise.