某些脉冲星发送脉冲比地球上最精确的时钟都准时。Some pulsars keep time better than the earth's most accurate clocks.他们发现了以往想象不到的新客体 —— 脉冲星 、 类星体和黑洞.They have discovered now , previou sly unimagined objects - pulsars, quasars, and black hole...
Liquidize the mixture and then pass it through a sieve.将混合物打成泥状，然后用滤网滤一下。The mixture can be used as a gargle several times a day.每天可用这种混合液漱几次口。Smooth the mixture with the back of a soup spoon.用汤勺的背面把混合料抹平。...
灰暗多云的天空a grey, cloudy day多云的天空中只见到一小块儿湛蓝.Only a tiny patch of blue was visible in the cloudy sky.在那多云的天上,只能看到孤零零的一颗星星.In that cloudy sky only one lone star could be seen....
上四年级时，他频频旷课。In his fourth year he was truanting regularly.每天早上,老师都记下学生们到校 、 旷课以及迟到等出勤情况.Each morning the teacher marks the pupils present , absent or late.旷课的学生占百分之几?What percentage of the students were absent?...