keep sth. a secret from sb.

例句：

1. 1. The team kept their secret until the end of the competition.
   队伍在比赛结束时才透露了他们的秘诀。
2. 2. She kept her promise to help him with his homework.
   她答应帮助他做作业，一直做到了最后。
3. 3. The company kept its employees happy by offering a generous bonus package.
   公司通过提供丰厚的奖金包来保持员工的幸福感。