One knows best what one has gone through with.

甘苦自知.

《现代汉英综合大词典》

You cannot appreciate the difficulty except through personal experience.

若非亲身经历,岂知其中甘苦.

《现代汉英综合大词典》

You don't know how difficult the job is, unless you have done it yourself.

没搞过这种工作, 就不知道其中的甘苦.

《现代汉英综合大词典》

The friends are faithful through thick and thin.

这些朋友历尽甘苦而忠贞不渝.

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True kindness presupposes the faculty of as one's own the suffering and joys of others.

真正的仁爱必定能够把他人的甘苦视同自己的甘苦.

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And many areas still suffer from salinity problems, dried up rivers and low water tables.

而许多地区仍然遭遇盐碱 、 河流甘苦和地下水位低等问题.

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