Would the police call for permission before dropping by to check out a crime scene?

警察去检查一个犯罪现场需要去请求允许吗?。

Put out a bowl of candy (unless, of course, you don't want colleagues dropping by). It's the office equivalent of a welcome mat.

放一盒糖果，除非你不想同事经常过来造访。这是办公室最受欢迎的礼物。

Populations of mammals, birds, reptiles , amphibians and fish have fallen off a cliff – dropping by 60 per cent in just over 40 years.

哺乳动物、鸟类、爬行动物、两栖动物以及鱼类的数量急剧减少，在过去的四十年里这些动物的数量减少了60%。

They also showed a slow decline in memory skills dropping by only one point in tests over five years when compared with five points for those who walked less.

他们向人们也通过试验证明，（常走路的人）五年中仅有仅百分之一缓慢记忆衰退，而走路少的人达到百分之五。