老师很感激教室里的志愿者助手。

The teacher was grateful for the volunteer ___helper in the classroom.

他提出在当地慈善活动中担任助手。

He offered to work as a ___helper at the local charity event.

当她的朋友搬家时，她经常充当可靠的帮手。

She often serves as a reliable ___helper when her friends move house.