自从她离开家后，她的自信心增强了。

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

充分的准备可以帮助你在面试前获得自信。

Good preparation can help you gain ___self-confidence before an interview.

他的自信让他能够清晰地阐述自己的想法。

His ___self-confidence allowed him to present his ideas clearly.