plain什么意思

plain [plein]n. 平原, 草原, 朴实无华的东西, 无格式adj. 简单的, 明白的, 平常的, 不好看的, 朴素的, 清晰的, 普通的, 平坦的, 十足的adv. 清楚地, 显然地例句：The problem is quite plain to us.那问题我们都很明白It is quite plain that he doesn't want to go.很显然他不想去speak plain明白地说。