这首诗她已全部背得滚瓜烂熟。

She has the whole poem off (by heart) already.

这演员把台词背得滚瓜烂熟了。

The actor has learned off his lines.

那个男孩将他学到的那首诗背得滚瓜烂熟。

The boy rattled off the poem he had learnt.

只有演员把台词背得滚瓜烂熟，我们排练戏剧才会有效。

Only when the actors have their lines (down) pat can we practice the play effectively.