单项选择题
I'll lend you my computer()you promise to take care of it.
A.unless B.while C.as D.if
单项选择题 I()half an hour before she came out of the telephone box and I entered.
单项选择题 Koalas(考拉熊) use a range of sounds to communicate with one another()relatively large distances.
单项选择题 The mother didn't know who()for the broken window.