... upflow filter 上流过滤器... upgradable computer可升级计算机... upgrade set 高层集...
双语例句
1
Computer software is easily upgradable and users have a choice between competing software platforms.
计算机软件升级很容易，用户可以在相互竞争的软件平台之间进行选择。
2
Create a new kids’ computer, an upgradable Wintel-compatible machine, in bright rugged colors that can take stickers and duct tape, and that a young user can call his/her own.