Collocations for extension - noun

planned, proposed
home, kitchen
one-storey, two-storey, etc.

add, build

extension to
They're building an extension to their house.

one-week, two-year, etc.
contract
The player has signed a five-year contract extension.

apply for, ask for, request
He's applied for an extension of his visa.

negotiate
get, receive
She got an extension for writing her essay.

give sb, grant sb
sign

considerable, great, major, massive (esp. BrE), significant
modest
further
This new job is a further extension of his role as a manager.

gradual
a gradual extension of the powers of central government

hair
Hair extensions make your hair look longer.

brand (business)
The company sees brand extensions as a means of tempting back customers.

logical, natural, obvious
The team appraisal is a logical extension of the individual appraisal interview.

by extension
The blame lies with the teachers and, by extension, with the politicians.