idiom: "it's not brain surgery!"
Today I was thinking of two idioms people use in English to say that something is not difficult, or it is not hard to find the solution. They might say:
"It's not rocket science!"
"It's not brain surgery!"
It means that rocket science or brain surgery are very difficult, but the thing they are referring to is not difficult.
How to use it?
"People need to wear masks whenever they are in public and stay 6 feet apart. It's not rocket science!"
It means you don't have to be very smart to figure out the solution to the problem.
Another idiom you may have heard of is "it's a piece of cake!" It means it's easy.
Example: "Did you take the test yet?"
"Yes, it was a piece of cake!" (it was easy)