i bought a new bike just now用just改写 i（ ）justi bought a new bike just now用just改写i（ ）just （ ）……

i bought a new bike just now用just改写 i（ ）just
i bought a new bike just now用just改写
i（ ）just （ ）……

I took a dictionary with me to school just in case.我带到学校一本字典,以防万一.