gift horse
Noun
Meaning
a gift (usually of inferior quality) that should be accepted uncritically
Source: WordNetHypernyms
Examples
Life is a gift horse in my opinion.
Never look a gift horse in the mouth.
On the other hand it was bad manners to look a gift horse in the mouth. Even if you're getting it from an overweight cracker in a fringe shirt.
They don't count the teeth of a gift horse.
One doesn't examine the teeth of a gift horse.
Don't look a gift horse in the mouth.