Waterfall model
[计] 瀑布模型
🧩 词语组成解析
🗣️ 情景例句
Why does it have to be one or the other?
为什么非得有这个就没有那个？
After dinner sit a while, after supper walk a while.
午饭后要坐，晚饭后要走。
No. The next development was to carve the characters on a piece of wood.
是的，不象。下一步的发展是将汉字刻在一片木板上。