back and forth什么意思？

She passed the needle through the rough cloth, back and forth.她一针一针地缝那块粗布。The prosecution and defense were bandying accusations back and forth.原告和被告你来我往，互相指责。Max zips back and forth across the living room.马克斯在客厅里快速地来回走动。...

back and forth的音标：back and forth的英式发音音标为：[bæk ænd fɔ:θ]back and forth的美式发音音标为：[bæk ənd fɔrθ]...