keep sb at arm’s length;maintain a discreet distance; neither too familiar nor too distant
❍ 夜间我们紧跟着敌人，～。At night we followed the enemy at a discreet distance.
不即不离
be neither too close nor too distant;hang about sb while keeping a certain distance;keep at arm’s length
不即不离bù jí bù lí
即：接近。离：远离、疏远。对待他人的态度既不太接近，又不太疏远。keep sb. at arm’s length, be neither familiar nor distant, be negatively friendly