They were in great need of help then. Therefore, your timely support certainly made a(n) _____.
| A．deal | B．difference | C．decision | D．effort |
【2015·天津】We need to get to the root of the problem______ we can solve it.
| A．while | B．after | C．before | D．as |
【2015·浙江】______ a single world can change the meaning of a sentence, a single sentence can change the meaning of a paragraph.
| A．Just as | B．Even though | C．Until | D．Unless |
【2015·重庆】If you miss this chance, it may be years ____ you get another one.
| A．as | B．before | C．since | D．after |
【2015·北京】_____the damage is done, it will take many years for the farmland to recover.
| A．Until | B．Unless | C．Once | D．Although |
【2015·北京】You won’t find paper cutting difficult _____you keep practicing it.
| A．even if | B．as long as | C．as if | D．ever since |