自信的英語單詞是confident，名詞形式是confidence。

confident

adj. 確信的，深信的; 有信心的，沉著的; 自信的;

n. 知己; 心腹朋友;

比較級：more confident 最高級：most confident 復數(shù)：confidents

[例句]

I am confident that everything will come out right in time我堅信一切終究都會好起來。

In time he became more confident and relaxed 。過了一段時間，他變得更加自信、更為放松。

I am confident in him. 我對他有信心。

I think people feel a bit more confident 我想人們應該覺得稍微自信了一點兒。

I admired him for being so confident at his age. 我欽佩他這般年紀就如此自信。