once 后面用哪种时态Once you have been working (这里为什么要用现在完成进行时,而不是用现
once 后面用哪种时态 Once you have been working (这里为什么要用现在完成进行时,而不是用现在完成时?)from home for a while,you might feel a bit lonely.It might be worth going into the office once or twice a week.
其实这两种时态有时候均可 现在完成进行时 强调动作的连续性 比如:我已经学英语学了七年了. I have been learning English for seven years.强调这七年来一直在学英语 动作的没有间断. I have learned English for seven years. 强调学英语学了七年了 更强调时间的长短.