weak star topology

例句：

1. 1. The old man is weak and needs help.
   老人虚弱，需要帮助。
2. 2. She was weak from lack of sleep.
   她因为缺乏睡眠而虚弱。
3. 3. The team's performance was weak in the final quarter.
   球队在最后一刻的表现很弱。