1.The human immunodeficiency virus -- HIV attacks and destroys CD4 cells making patients unable to fight off infection.
fight off 击退;排斥;竭力避免
He fought off three men who attacked him.
他击退了三个向他袭击的人 。
Did your husband manage to fight off his cold by taking aspirin?
你丈夫服用阿司匹林治好感冒了吗?
He's been fighting Nina off for years but she'll catch him in the end.
多年来他一直在躲避尼娜,可最终她总会撞见他的 。