Question

we were asked to gather ______ the teacher. (fill the appropriate preposition).Can't we write we were asked to gather ___before___ the teacher.

Answer 1

we were asked to gather by the teacher .
can't we write asked to gather much before to the teacher

Answer 2

We were asked to gather in front of the teacher.

We can also use "before"

You haven't specified whether the sentence is related to time or place.

We were asked to gather in front of the teacher. (This means we had to gather opposite facing the teacher)

We were asked to gather in front of the teacher. (This means we had to gather before the teacher arrived)

Hope This Helps You!