a doddle:

https://www.collinsdictionary.c...english/doddle

I can't read the Japanese sentence it's linked to, but how about:

With your ability it should be a doddle, but please don't get too big for your boots: apply yourself diligently like everyone in your class.

@JimBreen, @Pfirsichbaeumchen, @small_snow

I'll comment on #74480.

Fixed.

>With your ability it should be a doddle, but please don't be prideful of that but first apply yourself diligently with everyone in your class.

Is there be a reason not to change the text to sundown's suggestion or to something that preserves the use of "doddle" but is otherwise close to #11737702? Based on the comments already left here and elsewhere, I don't think any of the three of us likes the existing wording. To be specific:
:
- the use of "but" twice in the same sentence makes it hard to parse

- "be prideful of that" sounds worse than "get too big for your boots" or "be arrogant about it"

- "apply yourself diligently *with* everyone in your class" sounds less natural than "apply yourself diligently *like* everyone else in your class".

I use 11737702 instead of this one.