There is no greater pleasure than lying on my back in the middle of the grassland, _____at the night sky.A.to stare B. staring C. stared D, having stared
--- How is Dennis getting along with his work? --- Well, he could always _______ a new idea for increasing sales.
When he came to the door, my father ___ him at once although he was now a very old man.
–Do you mind my smoking here?--______.
This problem is not worth____ again.
Excuse me, but could you tell me ? I’d like to drop him a line.