Learn Hardcore Spanish (Latin America): El vídeo mostrará cómo la orquesta ensaya bajo la lluvia. - The video will show how the orchestra rehearses in the rain.

mostrará is the simple future tense (third person singular) of mostrar (“to show”), meaning “he/she/it will show” or “it will show.” It’s formed by adding the future ending -á to the infinitive:
mostrar + -á → mostrará
The alternative va a mostrar is a periphrastic future used for near or planned actions. The simple future (mostrará) often sounds more formal, general, or speculative.

Why does cómo have an accent here?

Because cómo introduces an indirect question (“how the orchestra rehearses”). In Spanish, interrogative and exclamative words always carry a written accent, even in indirect questions.

Why is vídeo written with an accent on the í?

vídeo is a three-syllable word (ví-de-o) stressed on the third-to-last syllable. Spanish rules require a written accent on antepenultimate-stress words, so the í carries the accent.

What does bajo la lluvia mean, and why not say en la lluvia?

bajo literally means “under,” so bajo la lluvia translates as “under the rain” or “in the rain.” Saying en la lluvia would be unnatural in Spanish, because you’re positioned “under” the falling rain rather than “in” it.

Why is the subordinate clause la orquesta ensaya in the present tense even though the main clause is in the future?

In Spanish, subordinate clauses keep the tense appropriate to their own timeframe. The video will show what the orchestra is doing (right now or habitually), so you use the simple present ensaya (“rehearses”). You’re not predicting a future rehearsal—you’re describing the action being displayed.

Why is there a definite article la before orquesta?

Spanish normally uses the definite article when referring to a group or institution in general. la orquesta means “the orchestra” as an entity. Omitting la here would sound odd.

What’s the difference between mostrar and enseñar, since both can mean “to show”?

Although both verbs can translate as “to show,” mostrar focuses on displaying or presenting something for observation or evidence. enseñar often means “to teach” or “to show how to do something.” In this context, mostrar is more appropriate because the video presents footage rather than teaching the rehearsal process.

Could we also say cómo ensaya la orquesta instead of cómo la orquesta ensaya?

Yes. In subordinate clauses introduced by cómo, the verb can precede the subject (cómo ensaya la orquesta) without changing the meaning. Both word orders are grammatically correct; the choice is largely stylistic.