27.How long do you think it will be________China becomes a rich and harmonious country?
| A．before | B．after | C．since | D．When |
This chemical material is very toxic. So put it ______ the children’s reach.
| A．by | B．beyond | C．within | D．from |
The central heating system of this office building is down and several workers ______ it right now.
| A．had repaired | B．have repaired | C．repaired | D． are repairing |
China's present environment situation is from bad to worse and if we _________ now to protect the environment, we’ll live to regret it.
| A．hadn’t acted | B．haven’t acted | C．don’t act | D．won’t act |
In recent years the consumption of aspirin _______ enormously in America.
A was increasing B. has increased C. had increased D. will be increasing
–Would you be kind enough to help me with my homework at one o’clock this afternoon?
-- . Will two o’clock be OK?
| A．Sure, it’s up to you | B．Sure, no problem |
| C．Sorry, I can’t make it | D．Sorry, I’m not available today |