I don't know if the report is true or not.这句话从英语语法上来看有没有错啊?急

I don't know if the report is true or not.这句话从英语语法上来看有没有错啊?急 I don't know whether it is true 【or not】.加不加 or not 有什么区别? I don't care if you think it is true or not,this little boy don't know if the story is true,but I will try to______it. He is very busy.I don't know if he will come or not tomorrow I don’t know ___________ he is well or not.whether/if,为什么? i don't know if i go to shanghai or not if i go to shanghai True or false I really don't know.True or false I really don If not you ,I don't know What's to be done.语法有错么 I don't know whether you will believe or not if i say i love Sometimes I really do not know,I love you is true,don't use He didn't know if he had passed the exam.这句话从语法上来讲对吗?didn't