1)They were working outside the spaceship when they noticed something strange.

Were they working outside the spaceship when they noticed something strange?

They were working outside the spaceship when they noticed something strange, weren't they?

2)At 4 p.m yesterday a small satellite was moving towards our space station.

When was a small satellite moving towards our space station?

At 4 p.m yesterday a small satellite was moving towards our space station, wasn't it?

3)The poet was looking at the sky when i touched his shoulder .

The poet was looking at the sky when I  touched his shoulder, wasn't he?

Was the poet looking at the sky when  I touched his shoulder ?

4) We were repairing the spacesuit when he came in.

 Were we repairing the spacesuit when he came in.

 We were repairing the spacesuit when he came in, weren't we?