If you start a path of one color you must continue to use only toe and handholds marked with that color.

VOA: special.2009.12.09

You can also use a "must" pattern when you're not talking about a person but you're talking about a situation.

当你不在谈论人物，而是在谈论情况的时候，你也可以用“must”句型。

Must 课堂 - SpeakingMax英语口语达人

you can use the "you have to" pattern to express something that somebody else really must do.

你可以用“you have to”句型表明一些其他人必须做的事。

have to 课堂 - SpeakingMax英语口语达人

You use the "must" in conjunction with another word.

你需要将“must”与其他的词连在一起使用。

Must 课堂 - SpeakingMax英语口语达人