面黄肌瘦的英文：
[Literal Meaning]
face/sallow/muscle/lean
with a sallow face and haggard shape

[解释]
脸色发黄，身体瘦弱。形容人营养不良或久病身体衰弱的样子。

[Explanation]
sallow and emaciated for malnutrition or chronicle disease

[例子]
从贫困山区来的孩子个个面黄肌瘦，很明显他们都是营养不良。

[Example]
The kids from poverty stricken mountains are all sallow and emaciated for malnutrition and obviously under nutrition.

[英文等价词]
emaciation with sallow complexion

He's a pale, skinny shrimp.
他是个面黄肌瘦的小个子。

You are as thin as a lath and as brown as a nut
看你面黄肌瘦，只剩下了一把骨头了。

Mrs. Bowdon was a little sallow woman with ratty brown hair
包登太太是一位面黄肌瘦的小妇人，梳着不太整洁的棕色头发。