size upgrade的意思是：大小升级；尺寸升级
例句：The superiority of this design is full-featured, small size, low power-consumption and easy upgrade.
该设计体现了功能齐全、体积小和功耗低等特点，有利于系统硬件升级。
upgrade 英[p?gre?d] 美[p?ɡred]
n. 向上的斜坡;
vt. 提升; 使（机器、计算机系统等）升级; 提高（设施、服务等的）档次; 提高（飞机乘客、旅馆住客等）的待遇;
[例句]You can upgrade from self-catering accommodation to a hotel.
您可以将自理膳食旅店升级为酒店。