EFL learners in two countries participated in two parallel experiments test
ing whether retention of vocabulary acquired incidentally is contingent on
amount of task-induced involvement. Short- and long-term retention of ten u
nfamiliar words was investigated in three learning tasks (reading comprehen
sion, comprehension plus filling in target words, and composition-writing w
ith target words) with varying "involvement loads"-various combinations of
need, search, and evaluation. Time-on-task, regarded as inherent to a task,
differed among all three tasks. As predicted, amount of retention was rela
ted to amount of task-induced involvement load: Retention was highest in th
e composition task, lower in reading plus fill-in, and lowest in the readin
g. These results are discussed in light of the construct of task-induced in
volvement.