Most of the vocabulary included in the Rosetta Stone American English Language Learning program is common English words used by native speakers on a regular basis. For example, the first core lesson begins with nouns for basic people of both genders (girl, boy, woman, man) as well as some pronouns and the definite article the. Other early lessons introduce the vocabulary for food, animals, and other objects as well as the indefinite pronouns a and an. Most of the vocabulary included is necessary words that beginning ESL students must learn. However, the section titled "Vocabulary Lesson" frequently did not introduce new words but instead reviewed the vocabulary from the previous section. Similarly, the same words and sentences were repeated to the exclusion of introducing more than a handful of new vocabulary per section.
Finally, the Rosetta Stone Online program also introduces new vocabulary without any explicit explanation and mixes too many new subjects at once. For example, although the first core lesson begins with some English pronouns, which are vital words for any beginning English language learner, the program fails to appropriately introduce the new subject matter. The simple subheading of "Pronouns" would have effectively alerted the learner to the topic focused on in the particular lesson.
The Rosetta Stone American English Language Learning program also sometimes mixes too many new vocabulary topics into one lesson. The section on numbers and colors, for example, is slightly confusing even for a native English speaker because the pictures to which the vocabulary must be matched often contain both numbers and colors. Overall, the vocabulary included in the program is appropriate for an English language learner but is confusing in organization and limited in content.