conceal|concealed

她几乎无法掩饰自己的恼怒。

She could barely ___conceal her irritation.

窃听装置被藏在一支钢笔里。

The listening device was ___concealed in a pen.

她设法对所有人隐瞒了她黑暗的秘密。

She had managed to ___conceal her dark secret from everybody.