飞机快起飞了。

Fēijī kuài qǐfēi le.

The plane is about to take off.

飞机准时起飞。

Fēijī zhǔnshí qǐfēi.

The plane took off on time.

飞机刚起飞的时候，我有点紧张。

Fēijī gāng qǐfēi de shíhou, wǒ yǒudiǎn jǐnzhāng.

When the plane had just taken off, I felt a bit nervous.