未知题型 Don't _________ your mother ________ everyday difficulties even if she is old.A separate;fromB keep;outofC insulate;fromD distract;from

未知题型 The defeated army gave up its weapons in ________ to the victors.A transmissionB emissionC missionD submission

单项选择题 由于测量过程中某些经常性的原因所引起的误差是() 。