do not know和don't know有什么区别?

i don't know what you mean和i don't know what do you mean 有区别 I don't know whether it is true 【or not】.加不加 or not 有什么区别? don't do和 not do有什么区别 两个简单的英语语法问题,I don't know和I didn't know有什么区别额? i wouldn't know 和 i don't know 有什么区别呢?只是委婉一点吗? didn't know,had't know和haven 't know用法有什么区别 i don't know 中do和know都是动词,有没有错误? Why not do 和 Why don't do 什么区别 know 和know about有什么区别 know和 know about 有什么区别? have no idea 和don't know有什么不同? Why don't do sth和 why not do sth有什么区别?