问题 填空题

哺乳动物是高等生物,地球上大约有4000多种,除极个别的种类外,都具有______、______等特征.

答案

哺乳动物的主要特征体表有毛,牙齿分化,体腔内有膈,心脏四腔,用肺呼吸,大脑发达,体温恒定,胎生,哺乳.胎生哺乳是哺乳动物在生长发育方面最突出的特征.大大提高了后代的成活率.鸭嘴兽是卵生但是哺乳.因此除极个别的种类外,都具有胎生哺乳的特征.

故答案为:胎生;哺乳.

阅读理解

阅读材料,然后从各小题所给出的四个选项中选出最佳选项。

      The word "Hello" may be used more often than any other word in the English language. Everyone in the USA

— and other countries — uses this word.

      Thomas Edison is believed to be the first person to use "hello" on the telephone soon after the world's first

telephone was invented.

      At first people began their words on the telephone with "Are you there?" They were not sure if a telephone

could really carry voices.

      Edison was a man with few words. He wanted to save time. The first time he picked up the phone, he was

very busy. He trusted (信任) the telephone as he invented it himself. He was sure someone was there and only

said "hello".

      From then on, "hello" is often heard when you pick up the telephone.

1. "Hello" may be used ________. [ ]

A. only in the USA

B. only in England

C. in many countries

D. in English-speaking countries except the USA

2. From the passage we can learn that Edison ________. [ ]

A. didn't like the word "hello"

B. didn't know the word "hello"

C. had nothing to do with the word "hello"

D. might be the first one to use "hello" on the telephone

3. At first people said "Are you there?" because _________. [ ]

A. they didn't trust the telephone

B. they didn't know each other

C. they couldn't see each other

D. they wanted to ask each other questions

4. Edison was a man of few words. It means ________. [ ]

A. he knew few words

B. He could say few words

C. He didn't like to talk much

D. He had few friends

5. Edison was sure someone was there because ________. [ ]

A. he could see the person

B. he knew the person

C. he invented the telephone and trusted it

D. he had just met the person

选择题