tight-lipped
沉默，缄默    

例句：
The company spokesperson remained tight-lipped about the arrangement for the takeover, and she refused to give out any information.
公司发言人对兼并一事的安排保持沉默，她拒绝提供任何信息。
 

take to one's heels
逃之夭夭
    
例句：
When police arrived, the thieves had already taken to their heels.
当警察赶到时，小偷们已经逃之夭夭了。

I'm glad to hear that.
听到这个消息我很高兴。 

对话：
A: We are making more profit this month.
B: Really? I'm glad to hear that.
　
A：这个月我们创造了更多的利润。
B：真的吗？听到这个消息我很高兴。