drink 指“喝酒”，drink like a fish字面意思是：像鱼儿喝水一样喝酒，可别理解成“小口喝，喝得少”恰恰相反，它表示酗酒、喝多、牛饮、如牛饮水、狂饮、痛饮。

【例句】
I used to drink like a fish and get drunk all the time.
我以前喝酒很猛，而且每次都喝醉。

My father used to drink like a fish, but now he drinks very little to keep healthy.
我爸爸以前经常酗酒，但现在他为了健康，很少喝酒了。