puckish

他顽皮的笑容让整个房间充满了欢乐的气氛。

His ___puckish grin brought a playful mood to the whole room.

那个小男孩露出顽皮的笑容，把姐姐的玩具藏在了沙发下面。

The little boy gave a ___puckish smile as he hid his sister's toy under the couch.