The present study used a within-subjects design to examine the effect of the type of written exercise on L2 vocabulary retention. Using input for the meaning and usage of the new words from a specially prepared minidictionary, university intensive English program students (n = 154) practiced target vocabulary in three types of written exercises conditions: one fill-in-the-blank exercise, three fill-in-the-blank exercises, and one original-sentence-writing exercise. An unannounced posttest using a modified version of the vocabulary knowledge scale tested the meaning of the word (L1 translation or L2 synonym) and usage of the word in a student-written sentence. A repeated measures ANOVA revealed that mean scores for the three exercise types were significantly different from each other, with words practiced under the three fill-in-the-blank exercises condition retained much better than those practiced under either of the other two exercise conditions. The findings suggest the important feature of a given L2 vocabulary exercise is not depth of word processing but number of word retrievals required. This result has implications for language teachers, curriculum designers, and, in particular, materials writers of traditional workbooks and CALL materials.