A _______ broke the newly-planted tree, ______ the planter feel very angry and sad.
| A．falling stone; made | B．fallen stone; and made |
| C．falling stone; making | D．fallen stone; to make |
We all can feel something unusual about Kate, but she just _________ let us know what it is.
| A．shouldn’t | B．mustn’t |
| C．needn’t | D．won’t |
I can’t imagine what air we would be breathing in if we __________ anything to stop air pollution.
| A．hadn’t done | B．didn’t do |
| C．haven’t done | D．don’t do |
Experts suggest that parents should let their child do tasks that he is physically and mentally capable of doing by himself, ______ will help to build a self-confident kid.
| A．that | B．who | C．which | D．what |
It’s recommended that our plan _____ until it was tested again.
| A．put off | B．be put off |
| C．should put off | D．would be put off |
The use of an alcohol breath test by the police greatly reduces the ____of drivers causing traffic accidents．
| A．possibility | B．pressure |
| C．preference | D．Production |