Questions & Answers about Во время матча они сидели тихо.
Why is the noun матч in the Genitive case (матча) here?
The phrase во время means 'during' and it always requires the following noun to be in the Genitive case. You can easily remember this by looking at its literal translation: 'in the time of' the match. That implied 'of' tells you to use the Genitive form матча.
Are во время (during) and вовремя (on time) the same thing?
No, they are different, which is a common mix-up! When written as two words, во время means 'during' and triggers the Genitive case. When written as a single word, вовремя, it is an adverb meaning 'on time' or 'punctually'.
Why do we use the imperfective verb сидели instead of a perfective form?
The preposition во время naturally sets up an ongoing block of time. Because the sitting was a continuous, uninterrupted state that happened throughout that period, we need the imperfective aspect сидели. A perfective verb would imply they completed the action of sitting down in a single, finished moment.