Definition: Rewrite each original sentence in order to make it easier to understand by non-native speakers of English. You can do so by replacing complex words with simpler synonyms (i.e. paraphrasing), deleting unimportant information (i.e. compression), and/or splitting a long complex sentence into several simpler ones. The final simplified sentences need to be grammatical, fluent, and retain the main ideas of their original counterparts without altering their meanings.
Input: Structure and rules A match between two opponents consists of up to eleven alternating rounds of boxing and chess sessions, starting with a four-minute chess round followed by three minutes of boxing and so on.

A match is between two people for eleven rounds. Each round is a four-minute chess round follow by three minutes of boxing.