Breakdown of Как только учитель закричал, дети убежали.
учитель
teacher
дети
children
как только
as soon as
закричать
to shout (perfective)
Questions & Answers about Как только учитель закричал, дети убежали.
Why are both verbs in this sentence in the perfective aspect?
The phrase как только (as soon as) highlights that one action happens immediately after another. Because these are completed, sequential events (first the teacher shouted, then the children ran away), we use the perfective aspect for both закричал and убежали.
What does the prefix за- add to the verb закричал?
The prefix за- here indicates the sudden start of an action. While the base verb means shouting, закричал specifically means suddenly started shouting or let out a shout, which perfectly fits the sudden trigger of как только.
How does убежали differ from the base verb for running?
The base verb for running in one direction is бежать. Adding the prefix у- makes it perfective and specifically adds the meaning of moving away or departing. So убежали translates to ran away or fled.
Is the comma after закричал mandatory?
Yes. In Russian, subordinate clauses like the one starting with как только must always be separated from the main clause by a comma.