It is hard for us to eat better, exercise more, and sleep enough, ________ we know we should.
| A．since | B．even if |
| C．unless | D．as if |
I＿＿＿＿＿＿often go fishing when I lived in the countryside.
| A．should | B．would | C．could | D．might |
Oh, Janne, you’ve broken another glass. You ought ＿＿＿＿when you washed it.
| A．be careful | B．to care | C．have cared | D．to have been careful |
Without electricity human life＿＿＿＿＿＿＿quite different today.
| A．is | B．will be | C．would have been | D．would be |
What would have happened＿＿＿＿, as far as the river bank?
| A．if Bob has walked farther | B．if Bob should walk farther |
| C．had Bob walked farther | D．if Bob walked farther |
—— Will you stay for lunch?
—— Sorry, ＿＿＿＿＿. My brother is coming to see me.
| A．I mustn’t | B．I can’t | C．I needn’t | D．won’t |