be | become

fully | emotionally, physically, sexually

fully
a fully matured cheese

early
This variety is easy to grow and matures early.

quickly, rapidly | slowly | emotionally, physically
The teenage years cover a period in which people mature physically and emotionally.

allow sth to, leave sth to
The cheese is smoked and then left to mature.

into
She had matured into a beautiful young woman.

to
a young man who is maturing to adulthood