in后面加语言、颜色的用法如下
1、in作为介词后面可以加语言、颜色。
2、in相当于谓语动词，谓语动词后加a+形容词以及名词。
3、在加语言、颜色时，固定用法in+颜色或语言。
例句
The hall was carpeted in blue.
大厅铺上了蓝色的地毯。
The route has been marked in red.
路线用红色标明了。
Spelling mistakes are circled in red ink.
拼写错误都用红笔圈了出来。
They walked among the crowds in Red Square.
他们在熙熙攘攘的红场散步。
