爬完五层楼梯后，他在门口大口喘着气。

After climbing five flights of stairs, he stood at the door ___huffing.

他气呼呼地离开了会议，因为没人听他的建议。

He ___huffed out of the meeting when no one listened to his suggestion.

青少年吸食胶水中挥发物质的行为非常危险。

Teenagers risk their health by ___huffing glue fumes.