唔該幫我檢查英文有沒錯!

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Furthermore, the racing cap has a print on its side, do you want to keep it ? If so, please advise which side(s) it should be printed on.

Remark : some words are rebundant in context. For instance, you want to "KEEP IT or CANCEL IT" ? In fact, simply asking "Do you want to keep it ?" is good enough.

THe other is "to keep or retain" - it has the same problem.

Furthermore, the racing cap has a print on the side of the cap, do you want to keep it or cancel it? Also, please advise which side or both sides of the print you want to keep or retain.