be, look, seem | become, get

extremely, very | a bit, fairly, quite, rather, relatively
The pass gets quite narrow towards the east.

be, seem | become

excessively, extremely, peculiarly, very | increasingly | comparatively, fairly, quite, rather, relatively, somewhat

in
people who are rather narrow in outlook

considerably | a bit, a little, slightly
The river narrows a little here.

sharply
The gap between the two parties narrowed sharply in the days before the election.

steadily

to
By the final round the gap had narrowed to three votes.

fractionally, slightly
Though her eyes narrowed fractionally, she made no comment.

suddenly | dangerously, shrewdly, speculatively, suspiciously, thoughtfully
The blue eyes narrowed thoughtfully.

against
Her eyes narrowed against the sun.

at
His eyes suddenly narrowed at the sight of her.

to
His eyes narrowed to slits.

with
His eyes narrowed with suspicion.