中暑：人体长时间暴露在高温或者强烈辐射环境中，引起以机体温度调节中暑功能障碍，汗腺功

根据首字母或中文提示提示写出句中所缺单词，注意使用正确形式

小题1:They took the children on field trips to o______________ plants and animals.

小题2:Mr Wang s_____________ his family by teaching evening classes.

小题3:His encouraging speech i______________ us to try again and never to give up.

小题4:Every morning little Peter d______________ newspapers from house to house. In this way, he can earn his school fees.

小题5: Yuan Longping had  s______________ for decades to find out a way to increase rice harvests and eventually he succeeded.

小题6:Some people began to buy the new house because the price has been r_________________.

小题7:Scientists have made many important _______________ (探索，发现).

小题8:Jane Goodall tried to make the rest of the world understand and _____________ (尊重) the life of these animals.

期前收缩的产生机制包括（）

A.附加的房室传导束

B.迷走神经张力增高

C.折返激动

D.触发活动

E.异位起搏点的兴奋性增高

为什么电瓶车控制箱必须固定牢固？

开发—销售模式主要适用于商品住宅开发项目和部分其他用途类型的开发项目，这种业务模式下的现金流入是( )。

A．销售收入
B．出租收入
C．利息收入
D．转售收入

人类物质生产史上第一次伟大飞跃是（）

A.原始畜牧业的出现

B.原始农业的产生

C.原始商业的开始

D.原始手工业的出现