He can sing a shaky note right (5)
I believe the answer is:
tenor
'he can sing a' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'shaky note right' is the wordplay.
'shaky' is an anagram indicator.
'right' becomes 'r' (common abbreviation).
'note' anagrammed gives 'teno'.
'teno'+'r'='TENOR'
Can you help me to learn more?
(Other definitions for tenor that I've seen before include "Placido Domingo, say" , "General meaning of a male voice" , "Pavarotti, maybe" , "Purport" , "Pavarotti, for example" .)