Laufer, Batia. "The Development of Passive and Active Vocabulary in a Second Language: Same or Different?" Applied Linguistics 19.2 (1998): 255-271.
Review by Jorge Pérez 

    This study tries to measure vocabulary knowledge of students of foreign languages using a quantitative and a qualitative approach. The author agrees with other studies in that there are degrees of vocabulary knowledge, and students learn words following a process that goes from passive to active knowledge. The study investigates three components of word knowledge: passive knowledge, controlled active knowledge, and free active knowledge. It analyzes the improvements of the three suggested types of vocabulary knowledge in a year of instruction in two groups of high-school students by means of three different tests already used by other researchers, which were proved to be efficient.

    Results indicate that passive and controlled active vocabulary have increased significantly in a year, but not free active vocabulary. Results lead the author to an interesting discussion in which she explores the relationship of the three types of knowledge. The passive and controlled active knowledge seems to be quantitative related, but there is not correlation with the third type. Even if students increase noticeably their passive and controlled active vocabulary, one cannot see a correspondent improvement in their free active vocabulary. The author makes several hypotheses to explain these facts in her discussion. For example, she mentions the grading conventions as a negative factor for students to improve their free active vocabulary in that they do not reward enough lexical variety, and students do not want to endanger their grades. In addition, she proposes a study with a larger amount of words to test if that will affect positively free active knowledge.

    All in all, this is an interesting study on this topic because, unlike other studies, it examines the overall improvement in the vocabulary of students and not only a set of words selected for the investigation. Furthermore, it is an innovating study in that it explores the improvements at different steps of the process of acquiring new vocabulary.