alacrity

他欣然接受了挑战，显得迫不及待。

He accepted the challenge with ___alacrity, showing his eagerness.

当慈善机构征集周末志愿者时，她毫不犹豫地举起了手。

When the charity called for weekend volunteers, she raised her hand with ___alacrity.

铃声一响，学生们就兴冲冲地冲向操场。

The students dashed toward the playground with ___alacrity as soon as the bell rang.