Description Who will buy Burt's dirt? The dirt was just dirt, but Burt was good as selling things. Then, the other animals get back at him for his trick. The phoneme /ir/ is featured in this title. In Level 4/5 - Blue/Green, children will practice their knowledge in this level, and will learn to read and spell words which have adjacent consonants (for example, trap, strong, milk, and crept).