Choose the correct answer A, B, C, or D.

It is important for Grade 12 students to keep ______ with the changes in the university entrance exams.
1. up
2. down
3. on
4. to
My father left his job because he couldn't put ______ with his colleagues' constant complaining.
1. on
2. through
3. along
4. up
The company is planning to cut down ______ staff to reduce costs.
1. in
2. on
3. at
4. along
Many teenagers find it difficult to live ______ to their parents' expectations.
1. up
2. back
3. on
4. in