Don't look a gift horse in the mouth
Don't look a gift horse in the mouth means don't be ungrateful when you receive a gift.
If someone tells you not to look a gift horse in the mouth, they mean that you should not criticize or feel doubt about something good that has been offered to you.
For example:
I know the car's not in great condition, but you shouldn't <em>look a gift horse in the mouth</em>.
<em>Origin:</em>
This comes into the category of phrases called <a href="http://proverbs.html/">proverbs</a>, short and expressive sayings, that are recognized as conveying some accepted truth or useful advice.
As horses age their teeth begin to project further forward each year and so their age can be estimated by checking how prominent the teeth are. The advice given in the<em> don't look a gift horse in the mouth </em>proverb is: when given a present, be grateful for your good fortune and don't look for more by examining it to assess its value.
