weakness的形容词形式

　　With such a weak heart she was lucky to come through the operation.

　　她的心脏很弱，手术后能活下来真是幸运。

　　The team's weak points are in defence.

　　这个队的弱点在防守。

　　She is still weak after her illness.

　　她病后仍然虚弱。