流体在作恒定流动时,流场中任意一点处的()、()、()都不随时间发生变化。
参考答案:压力;速度;密度
用所给单词的正确形式填空。
1. Let's (clean) the windows.
2. When's (he) birthday?
3. Now the children are (sing) the song.
4. Ben often (have) breakfast at seven in the morning.
5. Mike (not) like listening to music.
6. Do you like (collect) stamps?
7. We are (have) a birthday party.
8. There (be) a big cake and some candles.
9. Yang Ling's uncle (live) in a town near Nanjing.
10. He usually (go) shopping at Spring Festival.
将文件夹下LOLID文件夹中的文件FOOL.PAS的存档属性撤销,并设置为隐藏。