Now my Japanese student is having trouble understanding why these tenses are used and I’m not sure how to explain it.

1. My line manager wants the meeting arranged also, should I have brought a camera and ice and what if I have trouble with the line manager?

   Why does there have to be the use of arranged(!)?

2. As stock was being checked the staff worked in the evenings.

   Why do we use ‘was being checked’ in German definition rather than the verb was checked?

I know this is probably a very simple question but I’m terrible at explaining tenses to students. I know this is probably a very basic question. Is there any technical assistance

that can be provided?