1. By the time Jane gets home his aunt ______ for London to attend a meeting.

A. will leave B. leaves

C. will have left D. mind

分析：C。時間狀語從句中用一般現(xiàn)在時表示將來，by加將來時間與將來完成時連用。又如：

By May I will have got a new car. 到5月我將已買到一輛新汽車。

The old currency will have been phased out by 2020. 舊幣分階段至2020年將全部禁止流通。

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2. On her next birthday, Ann ______ married for twenty years.

A. is B. has been

C. will be D. will have been

分析：D。表示到將來某時（her next birthday）為止勢必會完成的情況，英語要用將來完成時，故選D。又如：

Don't worry. It's a storm in a teacup. Everyone will have forgotten about it by tomorrow. 別擔心，這不過是茶杯里掀風浪，到明天大家就都把這事給忘了。

If they succeed on Europe, then they will have reshaped the political and economic map of the world. 如果他們在歐洲獲得成功，他們將會改變世界政治和經濟格局。

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3. —I hear that Jason is planning to buy a car.

—I know. By next month, he _______ enough for a used one.

A. will have saved B. will be saving

C. has saved D. saves

分析：A。根據(jù)句中的by next month可知空格處應填將來時態(tài)，故可排除C和D；至于是選A還是B，則需根據(jù)句意來確定，由于前文已說“正準備買車”，說明存錢已經存夠了，故不宜選B。句意為：“我聽說詹森計劃要買一輛車?！薄拔抑?，到下個月，他積蓄的錢就夠買一輛二手車了?！?/p>