Research has shown that children who have English as a first language acquire grammatical morphemes in a predictable order. Many researchers claim that second language learners also follow a predictable pattern when learning English grammatical morphemes regardless of their linguistic background, and that the same mechanisms are responsible for both first and second language acquisition.

The aim of this paper was to study Swedish students’ knowledge of English grammatical morphemes, and to compare their knowledge with that of second language learners from other countries as well as with that of first language learners.

The results show that Swedish students seem to acquire morphemes in a similar way to that of second language learners in general and that they make errors similar to those made by first language learners. For example, the copula was almost fully acquired, while the third person regular and irregular constituted a problem for the students. The most notable exception was the possessive ´s, which Swedish students seem to acquire at an early stage compared to other second language learners.