Methods of learning words with or without deliberate attempts are known as the intentional versus incidental
learning in vocabulary research. While each approach has its merits and proponents, intentional vocabulary
learning is of particular interest to this study. According to Elgort and Nation (2010), deliberate techniques, such as
learning from vocabulary notebooks, word lists, and word cards, are useful approaches for achieving the
acquisition of second language (L2) vocabulary effectively and efficiently. Based on a series of experimental
studies, Elgort (2011) asserted that intentional learning of vocabulary is more efficient than incidental learning, as
the latter often requires long-term and extensive exposure to linguistic input, and such naturalistic language
learning conditions are not commonplace in English as a foreign language (EFL) contexts or other foreign
language learning environments. In contrast, intentional learning of vocabulary speeds up learners’ process of
lexical development due to focused repetition or memorization strategies, which can be completed individually in
a short period of time. It has also been argued that the retention rates of intentional vocabulary learning are
generally higher than those obtained with incidental learning (Hustijn, 2003), suggesting that deliberate attempts to
learning vocabulary are effective and worth the effort.