backman辅助工
backn.后面;背脊;靠背;后背;后卫vt.支持;后退adv.向后地adj.向后的;后面的;偏远的;过时的;积欠的
back-reflection photography背反射照相
backwashing three-way valve反冲洗三向阀
back-pressure steam turbine背压式蒸汽涡轮
Back up all your databases.备份您的所有数据库。
backed up type roller leveller带支承棍的辊式矫直机
backcross nucleus substitution回交核置代
back-to-chest acceleration背到胸加速度, 胸到背过载
backwash water of filter basin滤池反冲洗