Peter tried on three jackets, but _________ of them fitted him.
解释下列句子中划线的词语:
烽火连三月,家书抵万金
①烽火
国破山河在,城春草木深
②深
如图所示为一物体沿直线运动的位移图象(x﹣t图),根据图象所给信息,求: