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问题 问答题

在做“验证绿叶在光下制造淀粉”的中，

（1）为什么要把天竺葵提前一天放到黑暗处一昼夜？

（2）为什么要用黑纸片把叶片的一部分遮起来？

答案

（1）答：消耗叶片内的淀粉。

（2）答：使用黑纸片把叶片的一部分内不能进行光合作用，产生淀粉，便于对照实验。

完形填空

My biggest problem is that I’m too busy. When I was young, I ___ to have so much time, but these days I get up ____ and stay in school all day. Then I go right home and eat ___. Before I started high school, I used to spend a lot of time playing games __ my friends, but  I just don’t have the time anymore. In the evening, I used to ____ TV or chat with my grandma, but now I ____ to study. I love music, and my father used to take me to ___. These days, I hardly ever have time for concerts. I do my homework and go to bed. I really ____ the old days!

小题1:

A．came

B．went

C．used

D．wanted小题2:

A．late

B．early

C．quickly

D．slowly小题3:

A．nothing

B．something

C．dinner

D．breakfast小题4:

A．in

B．with

C．on

D．for小题5:

A．watch

B．turn on

C．see

D．turn off小题6:

A．need

B．have

C．try

D．start小题7:

A．cinema

B．club

C．school

D．concerts小题8:

A．hate

B．love

C．miss

D．think
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单项选择题

乙型强心苷苷元甾体母核中C-17位上的取代基是

A．醛基

B．六元不饱和内酯环

C．糖链

D．羧基

E．五元不饱和内酯环
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