a4
n. A4型纸（规格为297×210毫米的纸）
adj. A4型纸的
例句
A4: Many of them were hostile.
A 4：他们中的很多人怀有敌意。
A4 chip was a design issue. Other components different.
A 4芯片是一个设计问题，而其他部件不一样。
The bottom third of an A4 size sheet, for example, is more suitable.
而A4纸的页脚会更合适。
