weak trademark

例句：

1. 1. The old man is weak from lack of exercise.
   老人由于缺乏锻炼而身体虚弱。
2. 2. The baby was weak and needed extra care.
   婴儿虚弱，需要额外的照顾。
3. 3. The team's performance was weak in the crucial match.
   球队在关键比赛中表现不佳。