质疑探究:n. / v. 挑战 作动词时用于challenge ... to ...或challenge ... to do ...结构，意为"向......挑战......"。

The school challenged us to a game of football.

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The present world is full of challenges as well as opportunities.

challenging adj. 引发兴趣的，使人思考的，激发干劲的。

如：a challenging problem 发人深思的问题

总结提升:prepare v. , preparation n. 准备, 预备

prepare for prepare sb for

prepare to do prepare sb to do

be well prepared to do make good preparations for

make good preparations to do

be prepared for= be ready for

be ready to do(1) 　 (2)

　　课堂训练

I.单选

1. .Pieces of bamboo or wood______ into books.

A. used to be formed B. used to form

C. were used to forming D. used to be forming

2. ---Didn't you come yesterday?

A No, I did B Yes, I did C No, I didn't D Yes, I didn't

3. I _______ your making desserts after lunchtime.

　　课后作业

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