| Idiom | Meaning | Example | 
| fight fire with fire | 
fight with the same weapon the enemy uses
 | 
If he uses statistics, you use statistics. Fight fire with fire!
 | 
| fight tooth and nail | 
fight hard, fight like an animal
 | 
Canadian women fought tooth  and nail for the right to vote.
 | 
| fighting chance | 
(See a fighting chance)
 | 
 | 
| figure out | 
analyse and understand, discover why
 | 
Can you figure out why the car stalled? Is the gas tank empty?
 | 
| figurehead | 
a person who calculates but does not control
 | 
Shamir is just a figurehead; if you want a decision, see Ali.
 | 
| file 13 | 
the garbage can or wastebasket
 | 
This letter goes in file 13 - in the can in the corner.
 | 
| fill her up | 
fill the tank with gasoline, a fill-up
 | 
He drove up to the gas pumps and said, "Fill 'er up, please."
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| fill his shoes | 
do his work as well as he does
 | 
If Mia leaves, it won't be easy to fill her shoes. She does two jobs.
 | 
| fill in | 
complete by writing, write in the spaces
 | 
Fill in the blanks, please. Then give the form to Ms. Kiraly.
 | 
| fill in for me | 
do my job, do my work
 | 
Will you fill in for me while I'm  away? Just answer my phone.
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