Breakdown of La sentinelle vient de crier, elle aura peur.
elle
she
venir
to come
avoir peur
to be afraid
crier
to shout
Questions & Answers about La sentinelle vient de crier, elle aura peur.
Why is aura (future tense) translated as "must be" (present tense) here?
This is the "futur de probabilité" (future of probability) taught in this lesson. In French, you can use the future tense to express a strong assumption or deduction about something happening right now. The speaker hears the yell and guesses the current reason. In English, we naturally express this present assumption with "must be".
Why is it aura peur instead of sera peur?
If the sentry is a man, would it change to le sentinelle and il aura peur?
How does the phrase vient de crier fit into this assumption?
Venir de followed by an infinitive is the recent past, meaning "has just yelled." The sentence contrasts a confirmed, completed fact (the sentry just yelled) with an assumption about the present (she must be afraid). This contrast is a very common way to trigger the future of probability.