when

[FW]

Consider the following context:

I went into his room four times to check what he was doing. On all four occasions, I found him not doing his work.

Which of the following sentences can I use?

1-He was never working when I went into his room.

2-He would never be working when I went into his room.

3-He would never be working when I would go into his room.

4-He wasn't working when I went into his room.

5-He wouldn't be working when I went into his room.

6-He wouldn't be working when I would go into his room.

7-Every time I went into his room, he wasn't working.

[Tdol]

1- colloquially, yes
4- yes
7-yes

You could also say something like:
Every time I went into his room, I found him not working.