Highly praise English tax reforms being blocked by Left (5)
I believe the answer is:
exalt
'highly praise' is the definition.
(I've seen this before)
'english tax reforms being blocked by left' is the wordplay.
'english' becomes 'e' (abbreviation).
'reforms' is an anagram indicator.
'being blocked by' means one lot of letters goes inside another (I've seen this in other clues).
'left' becomes 'l' (common abbreviation).
'tax' is an anagram of 'xat'.
'xat' going around 'l' is 'xalt'.
'e'+'xalt'='EXALT'
(Other definitions for exalt that I've seen before include "Uplift in praise" , "Praise - latex (anag)" , "Praise, glorify or honor" , "Elevate" , "Laud" .)