10) The birth-rate in the developed countries eventually came down to a little above the death-rate, but only after a considerable lag.

发达国家的人口出生率只是在经历了很长一段时期之后，才最终降到略高于死亡率的水平。

11) The truth is difficult to come at.

真实情况很难获悉.

12) Whendid the color television came.

彩色电视是什么时候开始流行的？

13) As he was making his experiment he came across an interesting phenomenon.

他在试验时偶然发现一种有趣的现象。

14) These ink stains woun't come out

这些墨迹先不掉。

15) This year's crop has cow up to expectations.

今年的产量达到了预期的指标。

16) A protective coating is formed when aluminium and zinc come in contact with the air ,thus protecting metals from corrosion.

铝和锌接触到空气时，表面会形成一层保护层，从而保护它们免遭腐蚀。

17) Maybe much of the food people are going to need in the future will come out of the oceans.

未来人们所需要的大部分食物也许会来自海洋。

责任编辑：admin