All of them except for the 3rd sentence are correct :)
Answer:
Most likely teachers because they can talk to the principal about it. Also, it would be helpful to talk to parents so they can tell their kids and talk to other people about it.
Explanation:
:)
<span>It is either past perfect tense or pat progressive.
Example:
past perfect--- I had cooked when they brought the food.
past progressive---I was cooking when they brought the food.
Had cooked is past perfect, and was cooking is past progressive. Had cooked indicates cooking was finished, and wascooking indicates it was going on or in progress when something else happened (in the simple past).</span>
