| Idiom | Meaning | Example | 
| crack this case | 
solve a crime, discover who is guilty
 | 
David will crack this case;       he's a thorough investigator.
 | 
| crack under the strain | 
become irrational or hysterical due to strain, around the bend
 | 
Mother was a strong person. She never cracked under the strain of raising ten children.
 | 
| cracked | 
crazy, nuts, wacko
 | 
He must be cracked. He mailed a letter to himself.
 | 
| crackers | 
crazy, bonkers, nuts
 | 
Don't worry about me.  I've been crackers all my life.
 | 
| crackpot | 
a person who is strange or weird, wacko
 | 
Some crackpot wrote a letter to him threatening his family.
 | 
| crackup | 
collision, crash
 | 
Drinking and driving causes a lot of crackups.
 | 
| cramp your style | 
cause problems for you, cause stress for you
 | 
If we can't buy a Corvette, will it cramp your style?
 | 
| crank issue | 
a topic that causes anger, can of worms
 | 
The Premier raised a crank issue and then went on holidays.
 | 
| crank it up | 
turn up the volume, louder please
 | 
Hey, Karen, crank up the radio. That's a great song.
 | 
| crank out | 
make, write, manufacture
 | 
Can you crank out a few jokes for our school newspaper?
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