升国旗讲课怎么说英语

To teach about raising the national flag, you could say:
"Today we will be learning about raising the national flag. This is an important ritual that is often done at schools, government buildings, and other public places. It involves carefully and respectfully handling the flag, and following a set of protocols to ensure that it is displayed correctly. We will go over the steps for raising the flag, as well as the etiquette and symbolism associated with this act."