Mite in grass not moving (8)
I believe the answer is:
sticking
'not moving' is the definition.
('stick' is the opposite to 'move')
'mite in grass' is the wordplay.
'mite' becomes 'tick' (I can't justify this - if you can you should give a lot more credence to this answer).
'in' is an insertion indicator.
'grass' becomes 'sing' (I've seen this in other clues).
'tick' inserted into 'sing' is 'STICKING'.
Can you help me to learn more?
(Other definitions for sticking that I've seen before include "Adhering" , "Putting" , "ADHERENT]" , "in need of an oil, perhaps?" , "Gluing" .)