Questions & Answers about Когда заиграет гитара, мы запоём.
How does the prefix за- change the meaning of играть (to play) and петь (to sing) in this sentence?
The prefix за- here is an 'ingressive' prefix. It shows that an action suddenly or spontaneously begins. So заиграет means 'will start playing' and запоём means 'will start singing'.
Why is заиграет in the future tense if the English translation says 'starts playing'?
In English, we use the present tense after 'when' to talk about the future (When the guitar starts...). Russian uses the future tense because the action hasn't happened yet. Since заиграть is a perfective verb, its conjugated form automatically refers to the future.
The infinitive is петь (to sing). Why does the vowel change to ё in запоём?
The base verb петь has a stem change when conjugated: я пою, ты поёшь, мы поём, etc. Adding the prefix за- just builds on this exact same pattern to create the perfective future tense.
Why is the verb before the subject in the phrase заиграет гитара?
Russian word order is flexible. Putting the verb first in a dependent clause (like after Когда) is a very common way to set the scene. It emphasizes the sudden action of the music starting rather than focusing on the guitar itself.