1. According to the first three paragraphs,   ▲   .

A. the nanostructures can break down dirt and stains on clothes

B. the self-cleaning clothes easily wear out

C. the clothes will be covered with silver and copper after self-cleaning

D. people can use the self-cleaning clothes on rainy days

2. What does the underlined word “solution” in Paragraph 3 mean?

A. 方案        B. 模型        C. 溶液         D. 水盆

3. What do Paragraphs 4-5 talk about?

A. How the self-cleaning clothes are made.

B. How the self-cleaning clothes work.

C. What advantages the self-cleaning clothes have.

D. What helps the self-cleaning clothes work.

4. From the passage, we learn that   ▲   .

A. it’s time to throw out our washing machines   B. clothing makers like the solution

C. the solution sells well                D. the solution is not on sale yet

参考答案1―4、ACCD