1.The bird is singing ____ （在）the tree.
2.Does your cousin ____ （观察）birds?
參考答案:in(如果是从树上长出来的，就要用on)
observe: v. 观察,遵守,注意到
例句与用法:
1. I observed him entering the bank with a gun.
我看到他带着枪进了银行。
2. Do you observe Christmas?
你有过圣诞节的习俗吗？
3. The police have been observing his movements.
警方一直监视着他的一举一动。
4. `It may rain,' he observed.
‘可能要下雨, ’他说.
5. Do they observe Christmas Day in that country?
那个国家的人过圣诞节吗?
6. He observed that it would probably rain.
他说很可能下雨.
7. He observes keenly, but says little.
他观察敏锐, 但是很少说话.
8. We should observe the proprieties.
我们应该遵守礼节
