两个有关但又相互独立指标之比即为（）。 A.率 B.构成比 C.相对比 D.频率 E

It is not a good idea for children to have to work hard. Children should study in school as hard as they can. They should not have to do heavy work with their bodies. When parents or others force(强迫)their children to work hard, the results are never good. Many may be very bad. If a farmer makes his son work like a man, he may easily learn to hate farming.

Children sometimes do too much in gardens, in shops, or even in their own homes. They soon begin to hate such work with a force, because that can destroy their happiness. But there may be a worse loss, child’s love for its parents. The feeling may become something different. When that happens, the old kind of love never returns.

小题1:It is not a good idea for _______to have to work hard.

A．men

B．women

C．children

D．boys小题2:Children should study in school _______.

A．hard

B．easy

C．happy

D．early小题3:Children should not have to do _______work with their bodies.

A．easy

B．good

C．heavily

D．heavy小题4:The writer thinks children should study and play _______.

A．hard

B．happily

C．heavily

D．happy小题5:The writer thinks children’s parents or others don’t force their _______to work hard.

A．sisters

B．brothers

C．children

D．uncles

女孩，12岁，今年身高增长7cm，体重由原来的35kg增至41kg，并有月经来潮，检查发现 * * 开始发育，脂肪分布呈女性体态。

此期除进行营养指导，经期卫生指导，还应进行（）

A.遗传病诊断

B.基因测定

C.计划生育指导

D.心理指导

E.遗传咨询

一个电热器接在220V交流电路上，发热功率为800W，如果把它接在直流电路上，使其功率也是800W，则该直流电路的电压应是[ ]

A. 220V

B. 220V 

C. 110V

D. 380V

正丙醇

在神经一肌接头化学传递中，消除乙酰胆碱的酶是（）

A.磷酸二酯酶

B.腺苷酸环化酶

C.胆碱酯酶

D.ATP酶

E.单胺氧化酶