furtive

他偷偷摸摸地瞥了一眼手机，生怕被老师发现。

He cast a ___furtive glance at his phone, afraid the teacher would notice.

趁这家人转身拍照时，那只浣熊鬼鬼祟祟地一把伸向野餐篮。

The raccoon made a ___furtive grab for the picnic basket as the family turned to take a photo.

他偷偷摸摸地瞄了一眼同事的屏幕，以抄下销售数据。

He stole a ___furtive glance at his coworker's screen to copy the sales figures.