I have no use for the sad sack of a man.

叫他走吧，我不要这个不中用的人。

youdao

The blobfish is practically all face — a pale, gelatinous deep-sea creature whose large-lipped, sad-sack expression seems to be melting toward the floor.

水滴鱼实际上全身都是一张脸，这种苍白、胶状的深海生物长有大大的嘴唇，忧郁的表情似乎马上就要融化在地板上。

youdao

Are you a little tired of seeing the same sad-sack faces month in and month out?

每个月都看到同样一脸倒霉相的人，有点烦是吧？

youdao

And the unfortunate thing is that he was sort of a sad sack,un pauvre type.

不幸的是,他是一个冒失鬼,很可怜的那种

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Kraft loved the Patriots since the sad sack days of the 1970s and '80s.

FORBES: Magazine Article

He started off bemoaning the sad sack performance of the global economic.

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In the popular World War II cartoon strip The Sad Sack, the character was a naive, confused, lazy, bumbling private, but happy enough and almost lovable.

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