"You are alive."
Klingon verbs generally require prefixes to agree with their objects and subjects. In the sentence You are alive or You live, the subject is you (singular) and there is no object. That combination requires the prefix bI- on the verb.
Furthermore, you can almost always drop a pronoun when it is the subject or object of a verb. (Sometimes you keep it for clarity, if the subject or object wouldn't be clear.)
So the full sentence is bIyIn SoH, but since we usually drop pronouns as subject or object, we are more likely to say bIyIn. But yIn SoH is wrong because it lacks the required prefix.
The full chart of prefixes is here: https://en.wikipedia.org/wiki/Klingon_grammar#Prefixes
A perhaps more layman-accessible, but a little less complete, version is here: http://www.klingonwiki.net/En/Prefix
An explanation is given in the Tips & Notes, but I know it’s a lot of new information and some details are bound to be difficult to understand or slip through the memory. However, since Duolingo has hidden the Tips & Notes I want to make sure you know about them and where to find them. If you have not been reading the Tips & Notes, I would like to ask that you review those.
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