English ship with very good external polish (7)
I believe the answer is:
finesse
'polish' is the definition.
(both can mean impressive flair or style)
'english ship with very good external' is the wordplay.
I cannot really understand how this works, but
'english' could be 'e' (abbreviation) and 'e' is located in the answer.
'ship' could be 'ss' (prefix in ship names eg SS Great Britain) and 'ss' is found within the answer.
The remaining letters 'fine' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for finesse that I've seen before include "Subtlety, expertise" , "subtle tactic" , "Delicate handling of a situation" , "Subtle skill; bridge ploy" , "Subtlety in handling difficult situations" .)