furtive
adj
(a) done secretly and quietly so as not to be noticed 偷偷摸摸的; 鬼鬼祟祟的
a furtive glance 偷偷的一瞥
furtive movements 诡秘的活动.
(b) (of a person or his behaviour) sly or secretive, suggesting that one is guilty of sth or does not want to be noticed (指人或行为)躲躲闪闪的; 遮遮掩掩的.