Plain of厄斯垂伊伦plainadj.清楚的；简单的；坦白的；平常的；朴素的；纯的n.平原；广阔的区域adv.完全地；纯粹地plain text messages typing普通文本信息打字plain thread broaching tap普通螺纹拉削丝锥plain and simple reasoning浅近的道理plain lead-covered cable光皮铅包电缆Plain tidal river net work感潮河网plain bearing pillow bolck普通轴承轴台plain-coloured bed sheet素色床单plainclothes investigation便衣稽查plain embroidery traycloth平绣盘布plain of marine denudation海蚀平原