1.麻烦给个谚语：任何事情都有两面性

这些都是我写作的时候常用的.觉得不饶口也好记.

every coin has its two sides.

everything has its pros and cons.（这句比较口语一点）

is a two-edged sword.

是把双刃剑.

No garden without its weeds.

没有无杂草的花园（有利有弊）

everything has double folds.

every medal has its reverse.

补充问题的回答：

推荐用这句：

It is essential to examine every angle in order to fully understand the nature of a perplexing problem.

为了全面了解一个复杂问题的本质，很有必要从各个方面对事件进行调查.