A sentence in TV program
"My son is about as subtle as an elephant with gas."

There's something I don't understand:
1.an elephant with gas
2.Why is "about" added after "is"?

Thanks in advance :)

Question

A sentence in TV program
"My son is about as subtle as an elephant with gas."

There's something I don't understand:
1.an elephant with gas
2.Why is "about" added after "is"?

Thanks in advance :)

Answer

An elephant with gas is a very large animal that is farting constantly. Stinky and LOUD.

the "about" means that the son is almost as subtle as an elephant with gas, but not quite.