the penny drops

含义

someone finally understands something after a while

某人终于明白过来.

例句

1. 1I stared at the maths problem for ages, and then suddenly the penny dropped.
2. 2Sometimes the penny drops only when you try to explain the idea to someone else.
3. 3Leo didn't understand why we were laughing, but after a minute the penny dropped and he laughed too.
4. 4Some pupils need three or four examples of a new rule before the penny drops.
5. 5My sister explained the plot twice, but the penny dropped only when we watched the film again.

语法

作分句使用。只有 drops 变化形式：dropped、has dropped。the penny 保持单数。