I feel that it was time for me to ____.
| A．take actions | B．take an action | C．take the action | D．take action |
Brain, like muscles, also needs some kind of exercise and nutrition. The more you use your brain in the right direction, the more you ________ enhance your ability.
| A．could | B．might |
| C．shall | D．will |
We all know that we ________ our carbon footprint, but I suspect that many people wouldn't be prepared to go as far as Joan Pick, a retired scientist living in south London.
| A．must have reduced | B．should have reduced |
| C．may have reduced | D．could have reduced |
No matter how healthy you ________ be, you need to consult a doctor from time to time.
| A．should | B．will |
| C．must | D．may |
—May I smoke here?
—If you ________， choose a seat in the smoking section.
| A．should | B．could |
| C．must | D．may |
We can't use it to tie the goods because it ________ be broken at the weakest position.
| A．shall | B．may |
| C．can | D．would |