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 |
—Shall I attend my friend's comingofage ceremony, Mum?
—No, unless you see to ________ that you will be home before 1000 PM.
| A．one | B．this | C．it | D．her |
bought three DVD copies of the film Avatar and now _ is left. Somebody just borrows something and never returns.
| A．none | B．nothing | C．either | D．neither |
Jane is in a hurry because the train to the airport leaves _______ half an hour.
| A．by | B．in | C．for | D．until |
Staying up is bad _____ you , but getting up early is good _____ your health.
| A．for, for | B．to , for | C．to, to | D．for, to |
_______ one of you breaks the window will have to pay for it.
| A．Whoever | B．Whatever | C．Whichever | D．Wherever |