She hid her true feelings behind a shield of cold indifference.

　　她把自己的真實感情掩藏在一副冷漠的外表后面。

　　He hid his face in his hands.

　　他用手捂住了臉。

　　He hid behind a false identity.

　　他隱姓埋名。

　　She felt sure the letter had some hidden meaning.

　　她確信那封信中有言外之意。

　　There are fears of a hidden agenda behind this new proposal.

　　人們擔心這一新提議的背后有不可告人的目的。