Learn or develop

Formal written request signed by many people to appeal to authority to make change

A person who takes advantage of opportunity with little regard to moral principle

Crouch down in fear

Weakened; having a disability of a specified kind

State of being senile (of weak mental capacity)

Plateau

The scientific study of the mind

Having or showing lack of thought; empty

Lower in status or rank

A return to a former or less developed

The part of the mind of which one is not fully aware but which influences one’s action and feelings

Unable to read or write