Description Bonza the Monster . What is a good monster? Meet Bonza the monster and find out. Sing! Sing! Sing! . Bing can sing. Pong can bang. But who is louder? The phonemes /ear/air/ are featured in this title. In Level 3 - Yellow books, children build on the letter-sound combinations learned in levels 1 and 2. They learn consonant digraphs (sounds made up of two letters together such as 'ch' or "ll") and long vowel sounds (such as 'igh' or 'ai').