1） plump,bony,skinnyplump,丰满的.she is plump.
fat: 含有歧视的意义
he is bony. 含有贬义
bony skinny 均含有贬义
而thin勉强可以接受
slim 是一个褒义词
2）两个句子表达减肥
I am going on a diet.
go on a diet:节食
diet:保健食谱,特种饮食
I am supposed to be slimming.我需要减肥.
-Do you want some more?
-No, i am supposed to be slimming.
