The 75 Basic Phonograms explain 98% of English words.
The Advanced Phonograms unlock thousands of words that cannot be explained by the 75 basic phonograms. These phonograms are either very rare or used only in advanced vocabulary. Most of them are used in words derived or borrowed from another language.
pn is a Greek phonogram saying /n/ in pneumonia
cu is a French phonogram that says /k/ in biscuit and /kw/ in cuisine
e (sometimes spelled é) is a phonogram that says /ā/ in words from Italian and French, such as latte and café.
Advanced phonograms and their sounds do not need to be memorized for students to become strong readers and spellers. However, it can be helpful for students to become familiar with many of the advanced phonograms once they have mastered the seventy-five basic phonograms. This familiarity can both aid students in reading and writing words that use advanced phonograms and, in some cases, assist with comprehension by providing clues to the language origin of a word.