Choose the right grammatical form in each gap to complete the text

This is what happened at the station. I was going to the shops when I [saw|was seeing|see|had seen]Mr Kincel and his friend. They were going to the station and [wasn't see|weren't seeing |didn't see|hadn't seen]me.

When I came to the station, they were buying tickets. I hid behind the ticket office and asked someone to buy a ticket for me.

I [waited|was waiting |were waiting|had waited]for the train when I saw a cafe. I was thirsty, so I decided to go there. When I [entered|had entered|was entering|were entering]the cafe, Mr Kincel was drinking tea there. I hope he didn't see me! When the train arrived, I was drinking coffee. No time! I used the escalator to go down. The train was moving when I came to the platform. When I saw Mr Kincel and his friend through the window, they [looked|look|had looked|were looking] at the map.