Fill in the blank with the appropriate preposition:

The assignment must be submitted ___________ next Monday.

by

The correct answer is Option (4) - by

The preposition "by" is used to indicate a deadline, meaning the assignment must be submitted on or before next Monday.

"The assignment must be submitted by next Monday."

1. for:

   • Incorrect: "For" indicates purpose or duration and is not appropriate for deadlines.

2. in:

   • Incorrect: "In" is used to indicate a time period but does not work for specifying a deadline.

3. to:

   • Incorrect: "To" indicates direction or recipient and does not fit here.

4. by:

   • Correct: "By" is the correct preposition for specifying a deadline.