根据所给的首字母或中文提示写出正确的单词（必修4）

小题1:He was under o_____________（观察） by the police.

小题2:We have been told to show______________（尊敬）for our elders.

小题3:After a long ____________ (奋斗), he gained control of the business.

小题4:She r____________ her weight by 5 kilograms.

小题5:Could you e______________ the child for an hour, while I make dinner?

小题6:He had o____________ the difficulties with his English before he went aboard.

小题7:As you _____________ (接近) the school the first building you see is the teaching building.

小题8:Today many people are experiencing the joy of the a______________ park for the first time.

基础地质条件变化不大的地段，砌石路基的伸缩缝间距一般应约为( )。

A．6～10m
B．10～15m
C．15～20m
D．20～30m