妈妈看到我晚归时皱起了眉头。

My mom ___frowned when she saw me coming home late.

他皱着眉头思考明天的演讲内容。

He ___frowned while thinking about tomorrow's speech.

妈妈皱着眉头看着我，因为我把房间弄得一团糟。

My mom ___frowned at me because I made a mess in the room.