Complex sentence: It is also one of only three Mayan languages to have developed contrastive tone (The others are Yukatek and one dialect of Tzotzil) it distinguishes between vowels with high tone and vowels with low tone.
Split into simpler sentences: It is also one of only three Mayan languages to have developed contrastive tone (the others being Yukatek and one dialect of Tzotzil). It distinguishes between vowels with high tone and vowels with low tone.