This study focuses on foreign language vocabulary learning in computerized medium and seeks for any possibility of adaptation with respect to background information on word classes. To that end, we employ a spaced repetition flashcard software and display English vocabulary belonging to three word classes as (i) abstract noun, (ii) concrete noun, and (iii) verb. Regarding each word class, we deploy three sets of words with difficulty levels of (i) easy, (ii) medium, and (iii) hard. Through log file analysis, we derive several behavioral variables and examine the polyserial correlation between these variables and difficulty levels across different word classes. It is found that abstract and concrete nouns do not have any significant difference in terms of the correlation for the five kinds of behavioral variables in focus. However, it is noted that front sides of the cards involving verbs are observed relatively longer, while back sides are observed for somewhat shorter duration.