v.(使)变红；脸红
His acne begins to redden and intensify in less that five minutes. 他痤疮开始变红,并加大在不到五分钟。
The leaves turns yellow, the maples redden, so beautiful and so graceful! 树叶黄了,枫叶红了,煞是好看。
Humans redden when they are angry. 人类愤怒时会脸红。
