The rooms are crammed with humming Xerox machines.

　　那些房間里擺滿(mǎn)了嗡嗡作響的復(fù)印機(jī)。

　　Could you xerox this letter, please?

　　請(qǐng)復(fù)印一下這封信好嗎？

　　He kept the original copy and gave her only a Xerox.

　　他保留下原件而只給了她一份復(fù)印件。

　　Secondary xylem consists of pitted vessels, parenchyma fibers and rays.

　　次生木質(zhì)部由孔紋導(dǎo)管、薄壁組織及射線所組成。

　　The xylem of ferns and conifers contains only tracheids.

　　蕨類(lèi)植物和針葉樹(shù)的木質(zhì)部?jī)H含有管胞。