1. take precaution 采取防范措施
eg Although he was all smiles and jokes last night, he has been advised to take precaution while in public.
雖然萊特曼在節目上談笑風生,但是警方還是建議在公共場合采取保護措施。
2. stoop to v. 墮落;屈尊
eg He is a man who would stoop to anything for profit.
他是一個為了利益什么卑鄙勾當都干得出來的人。
3. at the time 在那時,那時候
eg They are the best estimates calculated from a selection of factors and can only be as good as knowledge at the time.
它們是根據一些經過選擇的因素計算出的最佳估計,而且可靠性只能與當時的知識一樣。