It's useless to worry about things that already happened and cannot be changed.

Right from the beginning; to do something from the start.

Someone who isn't witty or sharp, but rather, they are ignorant, unintelligent, or senseless.

Joe made the sugar cookies; Susan decorated them.

Typically said to indicate that any further investigation into a situation may lead to harm.

There was no ice cream in the freezer, nor did they have money to go to the store.