他愉快地吹着口哨走在街上。

He walked down the street, whistling ___cheerily.

尽管很疲惫，她还是欢快地唱着歌来鼓舞大家。

Though exhausted, she sang ___cheerily to lift everyone's spirits.

她开心地哼着歌走进了房间。

She walked into the room ___cheerily humming a tune.