?每枚硬币都有两面

Every coin has two sides. 每枚硬币都有两面；凡事皆有好坏。 No pains，no gains.

?事物都是一分为二的

... Many happy returns of the day. 长命百岁 Every coin has two sides. 事物都是一分为二的 Justice has long arms. 天网恢恢，疏而不漏 ...

?凡事都有利弊

... no news is good news. 没有消息就是好消息 every coin has two sides. 凡事都有利弊 every man has his taste. 人各有所好 ...

?事物都有两面性

事物都有两面性 ( Every coin has two sides ), 此释义来源于网络辞典。