- You can't take both of them.- You mean I ca...

- You can't take both of them.

- You mean I can choose_______ this one_______ that one?

A. not only; but also

B. either; or

C. neither; nor

D. both; and

九年级英语单项填空中等难度题查看答案及解析

- You can't take both of them.

- You mean I can choose_______ this one_______ that one?

A. not only; but also　　 B. either; or

C. neither; nor　　 　　　　 D. both; and

九年级英语单项填空中等难度题查看答案及解析

"You can't have both of them. You can choose 　　　 the kite 　　　 the toy car, " said the mother.

A. either; or　　 B. neither; nor

C. both; and　　 D. not only; but also

九年级英语单选题中等难度题查看答案及解析

You can't have them both. You can choose _______ the bike __________ the toy car.

A. either; or　　 B. both; and　　 C. not only; but also　　 D. neither; nor

九年级英语单项填空中等难度题查看答案及解析

Do you know viruses (病毒) and bacteria (细菌)? Both of them are very small, we can't see them with our eyes, and many people know nothing about them, In fact, there are a number of differences between viruses and bacteria. Bacterium, the singular form of the word bacteria, is a one-celled (单细胞) living thing, with complete sets of both RNA and DNA genetic codes (遗传密码). For viruses, some are sections of RNA, and the others are sections of DNA. So, bacterium is at least a hundred times larger than a typical virus.

One main difference between viruses and bacteria is the method of reproduction. A bacterium is a completely independent and self-reproducing unit. When the time is right, bacterium will divide its DNA and RNA genetic material in two. This is how bacteria live in almost every environment on Earth, including non-living things like rocks or plastic.

A virus, on the other hand, cannot reproduce without a living host. A virus may lie for thousands of years before finally coming into a suitable host. Once it enters the body of a host, a virus will get in the ling cell. Once inside a living cell, a virus takes the place of the living cell's DNA or RNA genetic instructions with its own. Those instructions are usually to make as many copies of the virus as possible.

Ninety-nine percent of all known bacteria are considered useful to humans, or at least have no bad influence. But most viruses, on the other hand, serve no good purpose. Their only purpose is to create more viruses in order to make themselves continue to live.

Bacteria are alive, which means they can be killed by some form of chemical things. Antibiotics (抗生素) can kill bacteria. Viruses, by comparison, are not considered living things. They cannot be 'killed' in the same way as antibiotics kill bacteria. In fact, any medicine is useless for virus' infections. The disease must run its course until the body can make a successful protection on its own.

九年级英语填空中等难度题查看答案及解析

---- Could you lend me a pen ?

---- Of course . Here are two and you can take ______ of them .

A. both　　　　　　 B. all　　　　　　　 C. any　　　　　　 D. either

九年级英语单项填空中等难度题查看答案及解析

—The books are so nice, which one can I take?

—Oh, you can take 　　　　　　 of them. I’ll keep none.

A.both B.all C.neither D.either

九年级英语单选题中等难度题查看答案及解析

—The books are so nice, which one can I take?

—Oh, you can take 　　　　　　 of them. I’ll keep none.

A. both　　 B. all　　 C. neither　　 D. either

九年级英语单选题中等难度题查看答案及解析

—The books are so nice，which one can I take?

—Oh，you can take ________ of them．I’ll keep none．

A．both              B．all            C．neither         D．either

九年级英语单项填空中等难度题查看答案及解析

If you can’t decide which of the two books to borrow, why don’t you take_____?

I won’t read them this week.

A.. all　　　　　　　　 B. any　　　　　　

C. either　　　　     D. both

九年级英语单项填空中等难度题查看答案及解析