The idioms in this exercise come from this article. Read the article and then try the exercise.
Instructions: For each number, a word is missing from the idiom. How many of the missing words can you identify?

1. I racked my ____, but I couldn’t think of a good topic for my research paper.

2. All the other students got mad when the teacher’s ____ reminded Mrs. Owens that she hadn’t given any homework.

3. Brett is a college professor now. Ironically, he was the ____ clown of our elementary school.

4. Dr. Schwartz isn’t going to let you retake the test you bombed. It doesn’t matter how much you kiss ____ to him.

5. Ricardo took Spanish in high school even though he’s a native Spanish speaker. Needless to say, he ____ through the course without any problems.

6. Finals are next week and I haven’t even started studying yet. I’d better ____ the books tonight.

7. Suzy has an impressive memory. She can recite dozens of poems ____ heart.

8. We can’t ____ an all-nighter without coffee. I’ll make us a pot.

9. Many people prefer to ____ the midnight oil and study at night. Others prefer to study during the day.

10. The present perfect tense used to be hard for me. It took me a while to catch ____.

11. Why do you think so many people drop ____ of college?

12. Matt never went to class and eventually flunked ____ of college.

13. If you’re putting yourself ____ school, you probably won’t have much time for extra-curricular activities.

14. I think I’ll sleep until noon tomorrow. I’ve been burning the ____ at both ends and could really use some rest.

15. Being a non-native English speaker, Karina struggled with English Literature. She was, however, able to pass all her math and science classes with flying ____.

16. The exam was a ____ of cake. We all received high scores.

17. I can’t figure ____ how to do the math homework.

18. I get lost in ____ whenever I’m doing something creative.

19. Students caught using ____ sheets will get a zero on the test.

20. Everyone wants to take Dr. Sullivan’s biology class. Everyone knows it’s a walk in the ____.

21. It’s a difficult riddle. If you want to solve it, you’ll have to put on your ____ cap.

22. Are teachers more likely to call ____ students who always know the answers?

23. I know her name, but I can’t think of it right now. I’m drawing a ____.

24. There’s a baseball game tomorrow at 2 p.m. We should play ____ and go see it.

For more practice, see the Practice Exercise section of the site.