自从她离开家后，她的自信心增强了。

Since she left home, her ___self-confidence has grown.

在我看来，原因是很多人不知道如何准备面试并获得自信心。

In my opinion, the reason for it is that not many people know how to prepare for an interview and gain ___self-confidence.

公开演讲可以帮助建立你的自信心。

Public speaking can help build your ___self-confidence.