Excellent grade for beginners (5-5)

I believe the answer is:

first-class

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'excellent' is the definition.
(I know that excellent can be written as first-class)

'grade for beginners' is the wordplay.
'grade' becomes 'first grade' (first grade is a kind of grade).
'for beginners' becomes 'class' (I can't explain this - if you can you should believe this answer much more).
'first'+'class'='FIRST-CLASS'

Can you help me to learn more?

(Another definition for first-class that I've seen is " Top flight".)

I've seen this clue in The Globe and Mail.

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