I dont know _____I should bring a present for my teacherA.what B.if C.how D.where选哪一个?

I dont know _____I should bring a present for my teacherA.what B.if C.how D.where选哪一个? i dont know f why?I dont know! i dont know her “i dont know chinese ” “I dont know !”是什么意思啊? i dont want to know It's time _____(play)games I dont's know my classmates very ____(good) i always knew looked formiliar (friends中的话)i dont know,that's why im asking i dont know,image i don i dont know who am i Dont+speak+English+I+dont+know+English甚么意思 1+1=?i dont know i dont know 的,号怎样打 hey i dont know chines engli i dont know who you are 三角函数万能解法i dont know I'm really shy and I just don't enjoy partise._____I don't know anyone there?A.what if B.how C.what's wrong D.why