They may be pale or yellow from serous exudates, or red form serum mixed with blood.

因含浆液性渗出液呈白色或黄色，混有血液则呈红色。

youdao

They may be pale or yellow from serous exudates, or red form serum mixed with blood.

因含浆液性渗出液呈白色或黄色，混有血液则呈红色。

youdao