Question 30: You have to study hard to _______ your classmates.

Explanation: keep pace with (phrV): catch up, on par with

Remaining answers:

get in touch with sb (phrV): who to contact

catch sight of sb (phrV): glimpse someone

look out for sb (phrV): watch out for someone, take care of someone

You have to study hard to keep up with your classmates.