New Words：

dust [dʌst] n. 粉尘；尘埃；尘土
dusty ['dʌsti] adj. 布满灰尘的；灰尘覆盖的

Sample Sentences：

She blew the dust off the book.
The books were all covered with dust.

The books looked dusty and unused.
Clean the dusty windows before you go home.
It was one of the driest and dustiest places in Africa.

New Words：

tear[ter] 撕裂;撕碎;扯破;戳破;
tore [tɔːr] tear的过去式

Sample Sentences：

I tore open the box.
Don't tear the paper.
Did you tear this book?
He tore a hole in his shirt.
He tore the letter in two（in half）.

New Words：

whether [ˈweðər] conj.（表示迟疑或两个可能性之间的选择）是否

Sample Sentences：

I'm going whether you like it or not .
I'm not sure whether I should tell you this.
He seemed undecided whether to go or stay.
I'll see whether she's at home(= or not at home) .

New Words：

prepare [prɪˈper] v. 准备;把…预备好;使(自己)有准备;

Sample Sentences：

I had no time to prepare.
How much food should we prepare?
He was in the kitchen preparing lunch.
I'm not prepared to discuss this on the phone.

New Words：

free [friː] adj. 自由的；免费的；随心所欲的；不受限制的

Sample Sentences：

I don't have much free time.
It's a free country; I'll say what I like!
The breakfast is free; you need't pay for it.
How much of their free time do you think children in your country spend on reading?