weak译为虚弱的,本身就是动词原形,详解如下。
动词原形是指使用英语时动词本身的形态,即与助动词或情态动词do, does, did, shall, will, should, would, may, might, can,could,must, need, ought to等一起构成谓语的动词时,要用原形。与助动词或情态动词do,does,did,shall,will,should,would,may,might,can,could,must,need,ought to等一起构成谓语的动词时,要用原形。