1。Bubbles,flaws,and other irregularities diffuse the light that passes through stained glass,____the glass sparkle.

A which making

B and making

C making

D to making

答案是c，我知道a,b都不对，可是d为什么不可以呢？c又是什么用法呢？

2 Boulder,Colorado, (is only)city in the United States (that) derives its (water supply) from (a) glacier.

答案选B，我觉得B没问题啊，反而觉得C怪怪的，supply是动词啊。

3 The Mississippi riverboat, which (evolved) from simpler (steamship) of the early 1800's, became the (dominant) form of (passenger transport) on the Mississippi River.

答案是B，是要加上s吗？但是D可以吗？怎么解释D呢？

4 A (single) bacterium has the (potential) to (produce) 16 million copies of (themselves) in a day.

答案是D，这个我选对了，不过不知道应该怎么改，还有就是反身代词的用法不太会。

5 Of 120 ( minerals known)to have been used (as gemstones), only about 25 are in (common use) in ( today jewelry).

答案选D， 可是我觉得应该是C，C里的use应该改成used.D错在哪里了？

请牛牛们指教。

C无非就是现在分词句末表示伴随结果

2 我怎么觉得应该选A呀！is the only city才对呀；supply可以是动词，也可以是名词，查一下字典就知道了，相似的还有food supply

3 加s；

transport n.

[uncountable]

British English

a system or method for carrying passengers or goods from one place to another

American Equivalent: transportation air/rail/road transport

Improved rail transport is essential for business.

commuters who travel on public transport (=buses, trains etc)

It's easier to get to the college if you have your own transport (=a car, bicycle etc) .

4 反身代词应该指代它的那个句子的主语，这里指代a single bacterium，改成itself

5 be in use a machine, place etc that is in use is being used Electric vehicles built in 1920 were still in use in the 1950s.

today's jewelry