The grammar of the first sentence seems wrong to me. yoH is a state verb, so it doesn't take an object. Is there a lesson that covers this type of grammar?
State verbs can follow nouns to act as adjectives of those nouns. The noun is not an object of the verb.
yoH be brave
SuvwI' yoH brave warrior
This use of adjectival verbs was first described in the Tips & Notes for the Dialogue Skill (the third Skill in the course) - https://www.duolingo.com/skill/kl/Dialogue-I/tips-and-notes. It gets covered again in the Adjectives Skill, but that is a later Skill than the Imperatives Skill that this sentence appears in. You have been introduced to a lot of information, so I'm not surprised if you have forgotten the information about using such "state verbs" as adjectives. Please go back and review the Tips & Notes in the Dialogue Skill.