Resume moves with a king in check (4,4)
I believe the answer is:
make sure
'check' is the definition.
('make sure' can be a synonym of 'check')
'resume moves with a king' is the wordplay.
'moves with' indicates an anagram.
'king' becomes 'k'.
'a'+'k'='ak'
'resume' anagrammed with 'ak' can make 'MAKE SURE'.
'in' acts as a link.
(Other definitions for make sure that I've seen before include "Establish beyond doubt, be certain" , "Ascertain" , "Put beyond doubt" , "Confirm" , "Put beyond risk" .)