Test in English before ten in the morning (4)
I believe the answer is:
exam
'test' is the definition.
('exam' can be a synonym of 'test')
'english before ten in the morning' is the wordplay.
'english' becomes 'e' (abbreviation).
'before' means one lot of letters go next to another.
'ten' becomes 'x' (roman numeral).
'in the morning' becomes 'am'.
'e'+'x'+'am'='EXAM'
'in' is the link.
(Other definitions for exam that I've seen before include "Students sit it" , "One taken by candidate" , "Set of questions evaluating skill or knowledge, in short" , "'Test, in short (4)'" , "Test (abbrev.)" .)