恍然大悟

wǒ men huǎng rán dà wù

我们恍然大悟。

We suddenly understood.

zhè shǐ tā huǎng rán dà wù

这使他恍然大悟。

This made him suddenly realize what had happened.

jīng tā yī zhǐ diǎn rén men cái huǎng rán dà wù

经他一指点，人们才恍然大悟。

When he dropped the hint, people suddenly saw the light.

kě néng cái dú le dì yī zhāng nǐ jiù huǎng rán dà wù

可能才读了第一章，你就恍然大悟。

You may find it in the very first chapter, you have come to understand suddenly.