ADJ by n
The 'achievable' group
These adjectives indicate that something may be or must be done by someone. The noun group following the preposition by indicates a person or a group of people.
achievable attainable deductible enforceable payable recoverable redeemable
Success at embroidery requires no special gift or talent. Rather, it is achievable by anyone who is willing to work hard and patiently.
This charge is normally payable by all students, whether British or of any other nationality.