Back and forth: noun An argument or discussion in which two or more people alternate in sharing their perspectives; adjective Moving first in one direction and then in the opposite one many times. As in The kids are outside throwing the baseball back and forth.
中文释义: 意思是“反复地，来回地”，就是你来回的从一个地方走到另一个地方再回来。词汇搭配用法：swing back and forth来回摆动，be back and forth:摇摆不定。back and forth 做副词用，后面可以再加副词。如：move back and forth quickly. 例句：He walked back and forth in the room, thinking about the problem. （他在屋里来回走动，思考着问题。）