Elizabeth believed the dog would die if ________ to her cruel owners so she kept it.
| A．returning | B．was returned | C．it would return | D．returned |
Chatting online can be _____fun, but kids must be sure they stay safe on _____web.
| A．不填; a | B．a; the | C．不填; the | D．a; a |
—What’s the matter with Tim?
—Oh. His electronic dictionary was left in a taxi accidentally, never ________ again.
| A．to find | B．finding | C．to be found | D．being found |
____ that caused him to serve dinner an hour later than usual.
| A．It was we being late | B．It was our being late |
| C．It was we were too late | D．It was because we were late |
China ________ a sharp increase in the number of aged people over the past decade.
| A．sees | B．saw | C．has seen | D．will see |