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What about cctv in classrooms as against corridors and playgrounds ?

为什么在教室安装摄像头而不是走廊或操场？

School playgrounds are hotbeds of crime and always have been .

学校操场是犯罪的温床，而且一直以来就是这样。

Sounds like the sort of riddle asked by ten-year-olds in school playgrounds .

这听起来像十岁小孩子在学校操场上问的那种谜题。

Like a new swear word sweeping across school playgrounds , suddenly everyone is talking about 200-day moving averages .

就像风靡学校操场的新脏话一样，突然间，大家都在谈论200日移动均线。

Workers can 't get to work or have to stay at home to look after children because lily-livered head teachers have decided icy playgrounds are dangerous .

工人们没法去上班，或者必须呆在家里照看小孩因为胆小怕事的校长认定，结冰的操场太危险了。