What's the key to teaching Grandma to suck eggs?

Richard, telling me that is teaching your grandmother to suck eggs.

On a side note, this is why closed networks suck eggs.

Next week we will have a report for grandmothers on how to suck eggs.

He did not like being taught to suck eggs by his grandchildren.

"Try to teach me to suck eggs, why don't you?"

They suck eggs when it comes to making their own fancy stuff.

To use a literary term, these three pages suck eggs.

"Perhaps later you can teach me how to suck eggs."

"If you try to teach your grandma how to suck eggs,you'll end up in trouble," Jake said.