短語(yǔ)詞組短語(yǔ)back -up galvanometer 輔助檢流計(jì)center back ride up 后中起吊weld back -up 焊縫背墊Back -up tongs 內(nèi)鉗backup and recovery 備份與恢復(fù)backup and restore 備份與還原backup system 備用系統(tǒng)；后備系統(tǒng)backup roll 支承輥；背輥；壓輥backup copy 副本；備份件backup file 備份文件backup software 文件備份backup device 備份設(shè)備；備用設(shè)備full backup 全部備份system backup 系統(tǒng)備份；系統(tǒng)后備backup storage n . 后備存儲(chǔ)器file backup 文件備份；檔案?jìng)浞?/li> 返回 back up