Collocations for slow - adj.

be, prove, seem | remain

extremely, incredibly, remarkably, very | interminably | a bit, comparatively, fairly, a little, pretty, quite, rather, relatively | agonizingly, desperately, frustratingly, painfully, tediously, tortuously
Filming was painfully slow.

notoriously
Civil court proceedings are notoriously slow.

noticeably
He was noticeably slow to respond.

necessarily
Genetic evolution is necessarily slow.

at
They are extremely slow at reaching decisions.