Backal口腔锭
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 painting底面涂漆
Back to Lenin回到列宁
backdoor file秘密文件
back the oars倒着划浆
back charging背后冲撞
backsiphonagen.反虹吸;回吸;反吸
backing store存储器回填,辅助存储器,后备存储器
backscattered反(背)向散射的
backwall cell后壁光电池
"he got his job through the back door"