The 74 basic phonograms identified in Uncovering the Logic of English originate from the 70 basic phonograms identified by Dr. Orton. After doing an extensive word study, Logic of English expanded the original list by adding the following phonograms: augh, bu, gu, and cei.
For more information, see our blog: Why 74 Phonograms?
In 2018, we began teaching the noun and verb suffix -es as a phonogram, bringing the total number of phonograms we teach to 75. Learn more about ES.