Satisfy that teas have improved (4)
I believe the answer is:
sate
'satisfy' is the definition.
(I've seen this before)
'teas have improved' is the wordplay.
'teas' anagrams to 'SATE'.
However, I am not sure how the anagram is indicated.
'that' acts as a link.
Can you help me to learn more?
(Other definitions for sate that I've seen before include "Supply to full capacity" , "Fill to repletion" , "cloy" , "Overfill, gorge" , "Fill completely" .)