Dime a Dozen
= something that is very common, easy to find, so it doesn’t have much value
( dime [U.S. coin = 10 cents -> 1/10 of a $1) , (dozen = 12 items)
Ex: In America, fast food restaurants are a “dime a dozen.” You can find them everywhere.
Ex: In Los Angeles, young people trying to become actors in Hollywood, are a “dime a dozen.” There is many of them.
