It happened a long time ago.

这发生在很久以前。

Yes, I have, but a long time ago.

是的，我去过，但很久以前了。

But they take a long time to grow.

但它们需要很长时间才能长大。

Food can be preserved for a long time.

食物可以保存很长时间。

A long time ago, people built pyramids.

很久以前，人们建造了金字塔。

For a long time John did not feel well.

约翰很长时间都感觉不舒服。

Dinosaurs were on Earth a long time ago.

恐龙很久以前在地球上。

A long time ago children wrote on slates.

很久以前孩子们在石板上写字。

There were dinosaurs here a long time ago.

很久以前这里有恐龙。

I flew to the earth in it a long time ago.

我很久以前乘它飞到了地球。