This study investigated the use of the adverb takusan, using the International Corpus of Japanese as a Second Language (I-JAS). Based on previous studies’ analyses of takusan, we divided the learner's example into three types: (1) a large amount of nouns, (2) a large amount of movement, (3) a use as a degree adverb. Comparing Korean learners’ usages with those of native Japanese speakers, we explored the errors made by Korean learners in the use of the adverb takusan.
First, we found that the use of a large amount of nouns is a typical usage of the adverb takusan. This type can divide into the example means that the abundance of the subject is large and the example means that the abundance of the object is large. An example of the abundance of a subject are co-occurred with existence verbs, or subject change verbs that do not develop change, or subject action verbs. In addition, we found that the learner produced an unnatural example by co-occurring the negative form of the existence verb, or by co-occurring the subject change verb which means the progressive change.
Next, we found that the example of a large amount of movement has the subject which lexical meaning is not many or large, and the example of takusan co-occurring with the subject movement verb indicates. But there were some examples showing the frequency of movement.
Finally, we found that the learner is using the adverb takusan as a degree adverb, and it is unnatural for the co-occurrence of the adjective and the adverb takusan. And it is unnatural for the co-occurrence of subject change verb which mean progressive change and the adverb takusan, too.