问题 问答题 简答题

选择固沙植物种一般要通过哪几个方面的研究?其中哪一方面的研究是必不可少的?为什么?

答案

参考答案:

(1)根据植物种生理、生态特征选择

沙区生境特点是风蚀沙埋严重,干旱、贫瘠、沙面高温,许多植物从形态上,生理上对此有所适应

(2)以植物演替规律作为借鉴

自然界流沙固定的过程在某种意义上来说就是人工固沙的样板,各阶段的代表可以作为我们人工选择优良固沙植物种的借鉴。

(3)进行栽植实验,反复验证(此为最主要,且必不可少的)

实践是检验真理的唯一标准,选择固沙植物种必须进行栽植试验,验证植物种选择

适当与否最可靠的办法就是通过栽植试验。只有成活率高,生长正常的植物才是良好的固沙植物。

阅读理解

Read and choose. (选择正确的答案) 

     Bob is a middle school student. He studies in a middle school in the east suburbs (郊区) of California.

Bob goes to school from Monday to Friday. On weekdays, he always gets up at 7:00 o'clock, then he

has breakfast. He usually has a cup of milk, a piece of bread and two fried eggs for his breakfast. At

about 8 : 00 0'clock, he gets into his father's car and his dad drives it down the road towards his school.

Classes begin at 8 :30 and at 12 :30, he goes to the school canteen for lunch. In the afternoon,  when

classes are over,  Bob usually plays basketball with his classmates. Sometimes he also goes to the school

library to do some reading. In the evening, Bob may either watch an interesting TV program or do some

Internet surfing(冲浪). He goes to bed at 10 :00. His school days are busy, but he always enjoys them

very much.

1. Where does Bob live?          

A. He lives in a school.

B. He lives in California.

C. He lives in China.

2. How many days does Bob go to school in a week?              

A. Seven days.          

B. Six days.          

C. Five days.

3. Does Bob go to school by bus?           

A. No, he doesn't. His father drives him to school.

B. Yes, he does.

C. No, he doesn't. He goes to school by bike.

4. What does Bob do after classes?              

A. He goes home.

B. He plays basketball everyday.

C. He usually plays basketball and he also goes to the library.

5. Does Bob like his schooldays?              

A. Yes, he does.

B. No, he doesn't.

C. Just so-so.

6. What's the Chinese meaning of the word "canteen" ?           

A. 搡场                

B. 餐厅            

C. 图书馆

选择题