By the time she reached the corner of the street, the footsteps _________.A．had

题型：不详难度：来源：

By the time she reached the corner of the street, the footsteps _________.

A．had gone

B．were gone

C．are missing

D．have disappeared

答案

解析

略

举一反三

Up to now, the weather______ pleasant for the journey. I hope our good luck will continue.

A．is

B．was

C．has been

D．will be

题型：不详难度：| 查看答案

. Jane Goodall with her assistants ______ for the forests to learn more about the chimps.

A．are setting off

B．is setting off

C．have set off

D．sets off

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His daughter was disabled after a serious illness in 2003 and in the last seven years, he
money to help those children like his daughter.

A．has raised

B．has been raising

C．had raised

D．was raising

题型：不详难度：| 查看答案

With the rapid growth of population, the city______ in all directions in the past five years.

A．spreads

B．has spread

C．spread

D．had spread

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. By the year 2020 scientists _____ a lot of research on AIDS.

A．had done

B．do

C．are doing

D．will have done

题型：不详难度：| 查看答案