Lots of sheets are wasted on manuscript (5)
I believe the answer is:
reams
'lots of sheets' is the definition.
'reams' can be an answer for 'lots' (I have seen 'Lots of paper ' mean 'reams' so perhaps 'lots' could also mean 'reams'). I am unsure of the 'of sheets' bit.
'are wasted on manuscript' is the wordplay.
'wasted' indicates an anagram.
'on' means one lot of letters go next to another.
'manuscript' becomes 'ms' (abbreviation for manuscript).
'are' with letters rearranged gives 'rea'.
'rea'+'ms'='REAMS'
Can you help me to learn more?
(Other definitions for reams that I've seen before include "Scrapes the barrel" , "a very large amount" , "This much paperwork" , "Large quantity of written matter" , "Large quantities (of paper?)" .)