______ others in the reading room, Jack walked in on tiptoes.
| A．Not disturbing | B．To not disturb |
| C．Not to disturb | D．Not having disturbed |
Can you tell us what horses _______?
| A．feed on | B．live on | C．feed by | D．live by |
He said that he didn’t know ______ to deal with the matter, so I left.
| A．what | B．when | C．where | D．how |
The way of life he was used to _______ when he came to study in America.
| A．change | B．changed | C．changing | D．being changed |
He said that we should protect the ancient civilization from _______.
| A．losing | B．lost | C．being lost | D．to lose |
She told us what she bought yesterday ________ a few apples and some clothing.
| A．is | B．are | C．was | D．were |