问题 填空题

聚丙烯酸盐采用它的铵盐或钠盐50个单体为解凝剂,()个单体稠化为粘结剂500000个单体为絮凝剂。

答案

参考答案:5000

判断题
阅读理解

阅读理解。

     Plants are very important living things. Life could not go on if there were no plants. This is because plants

can make food from air, water and sunlight. Animals and man cannot make food from air, water and sunlight.

Animals get their food by eating plants and other animals. Therefore animals and man need plants in order to

live. This is why we find that there are so many plants around us. If you look carefully at the plants around

you, you will find that there are two kinds of plants: flowering plants and non-flowering plants. Flowering

plants can make seeds. The seeds are protected by the fruits. Some fruits have one seed, some have two,

three or four, and some have many seeds. But a few fruits have no seeds at all. An example of a fruit without

seeds is the banana fruit. Most non-flowering plants do not grow from seeds. They grow from spores (胚芽).

Spores are very small. Some spores are so small and light that they can float in the air. We may say that spores

are quite the same as seeds. When these spores are all on wet and shady places, they usually grow into new

plants.

1. The main idea of the first paragraph is that _____. [ ]

A. plants are important for life

B. plants cannot grow without air

C. there are many plants in the world

D. we can not live without water

2. Plants can make food from _____. [ ]

A. flower, water and air

B. water, sunlight and air

C. air, water and soil

D. air, sun and light

3. What can we infer (推断) from the passage? [ ]

A. Of all living things animals are most important

B. Spores are seeds

C. All fruits of flowering plants have seeds

D. Without plants, man will die out

4. This passage may be taken from _____. [ ]

A. a medicine book

B. a novel

C. a science magazine

D. an experiment report