the study of rocket. 那个实验的成功证明我们在火箭方面的研究取得很大成就。

3．The university has achieved all its goals this year. 这个大学今年已经实现了所有的奋斗目标。

［即学即用］

Jack London worked very hard and finally he _______ his goal.

A. made B. found C. developed D. achieved

Key: D

6．used to do

used to do 过去常常做某事

　be used to do 被用来做。。。

　be/get used to doing sth./ sth. 习惯于/开始习惯于做。。。

　there used to be 某地过去有某物

[即刻点击]

1．There _________ a swimming pool in our town. 我们镇上过去有一个游泳池。

2．In our school, candles　＿＿＿＿ give light when electricity is cut off. 在我们学校，停电时，就用蜡烛来照亮。

3．I _________ traveling by air and only on one occasion have I ever felt frightened.

我习惯了乘飞机旅行,只有一次我可给吓怕了。

Key: used to be; are used to；am used to

1. challenge

challenge n./v. 挑战 challenging adj. 引起挑战性兴趣的

1. He challenged me to play another tennis game. 他向我挑战要我跟他再打一场网球。

2. The present world is full of challenges as well as opportunities. 当今社会充满了机遇与挑战。

2. free

adj. 免费的；空闲的

a free meal. 免费的一餐 for free 免费的 free time 空闲时间

1．The girl 'gave' her mother a free dress once a week! 这个姑娘每周`给'她妈妈