My sister is talking _____ her cell phone. 填哪个介词?理由?

My sister is talking on the phone________________________划线部分提问is talking on the phone划线 My sister is talking _____ her cell phone. 填哪个介词?理由? The girl talking my teacher is my sister 为什么要用talking 可是它前面没有is 所以应该用talks she is my sister. My sister is a my sister is a My sister is a my sister is my sister is my sister is zhangjing is my sister. my sister doesn't like talking to others.she is very( ）以s开头的字母 My parents'?is my sister? Lily is my sister.I have()sister 作文My sister is room my sister is good . maths （this）is my sister 就这1.Look!My mother is talking with my sister o____ the phone1.Look!My mother is talking with my sister o____ the phone2.Do you like the movie?S___,it's very interesting.3.Are your friends r___ books in your room4.You can w___for me in front of th