Breakdown of Kommt eine hohe Welle, halten Sie sich bitte fest!
ein
a, an (eine)
kommen
to come
Sie
you (formal)
bitte
please
Questions & Answers about Kommt eine hohe Welle, halten Sie sich bitte fest!
Why does the sentence start with the verb Kommt instead of the word Wenn?
This is a verb-first conditional clause. In German, you can drop wenn (if) and move the conjugated verb to the very beginning of the sentence. It means the exact same thing as Wenn eine hohe Welle kommt.
Why is halten right after the comma? Doesn't the verb usually come second?
It is in the second position! The entire first clause (Kommt eine hohe Welle) acts as one single block occupying position one for the main sentence. Therefore, the main verb (halten) must come immediately after the comma to take position two.
What verb does fest belong to at the end of the sentence?
It belongs to the separable verb sich festhalten (to hold on tight). Because it is a separable verb, the prefix fest gets pushed to the very end of the clause. The sich makes it reflexive, literally meaning to hold yourself tight.
Why is the word order halten Sie if this isn't a question?
This is the formal imperative (command) form. To give an instruction to someone you address with Sie, you put the verb first, immediately followed by the pronoun. Adding bitte makes it a polite request.