altruistic behavior

例句：

1. 1. He isan altruistic person who always putsothers' needs before his own.
   他是一个利他主义者，总是把别人的需要放在自己的前面。
2. 2. The altruistic act ofdonating blood has saved many lives.
   无私的行为捐献血液挽救了许多生命。
3. 3. She wasdeeply moved by the altruistic gestureof her friend.
   她被朋友的无私举动深深感动。