短语词组短语I drop you line 你系我滴drop me line 写信给我drop contour line 液滴外形轮廓drop out line 紧急放空线drop in line 落伍drop a line 写信;写信给某人;垂钓Drop -Line 线图;垂线图;垂线形图;垂直线图Drop sb line 写信to drop in line 落伍 返回 drop line