英文之旅

老化的核反应堆早晚会出事故。
An ageing nuclear reactor is an accident waiting to happen.

但往往在现实中，或是胆小羞怯，或是掩人耳目，或是别有用心，不得不有意装作无意。

她刚好在我们正要离开时到达，但我不能肯定这是出于偶然还是有意安排。
She arrived just as we were leaving, but whether this was by accident or by design, I'm not sure.

这个就可以用习语“conspicuous by your absence”来表示本应在场时“因缺席而招人注意”。