Translation of "9am" in Chinese

This shop is open from 9am to 6pm.

这家店从9点开到18点。

We start class at 9am, but he came as early as 8 o’clock.

我们早上九点上课，可是他八点就来了。

- This shop is open from 9am to 6pm.
- This shop is open from 9 to 6 o'clock.

- 这家店从9点开到18点。
- 这家店从早上9点开到午后6点。