既然强调“由你”二字,可否这样考虑：随你的便、那是你的事...之类表述?
1.Believe it or not,it's up to you.Anyway I do(或：I do believe、I believe,相较而言个人倾向I do).
2.Whether to believe (it) or not is your affair.Anyhow I do.
3.Believe or not.It is your business.As for me,I do.
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