Crossword Genius

Teach girl badly, being exceptionally drowsy (9)

Ross

I believe the answer is:

lethargic

'exceptionally drowsy' is the definition.

'teach girl badly' is the wordplay.
'badly' is an anagram indicator.
'teach'+'girl'='teachgirl'
'teachgirl' is an anagram of 'LETHARGIC'.

'being' is the link.

(Other definitions for lethargic that I've seen before include "The garlic (anag.)" , "Sluggish and apathetic" , "Unenergetic" , "Lacking in energy or vitality" , "without energy" .)

I've seen this clue in The Times.
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