Although it is widely acknowledged that collocations play an important part in second language learning, especially at intermediate-advanced levels, learners' difficulties with collocations have not been investigated in much detail so far. The present study examines ESL learners' use of verb-noun collocations, such as "take notes," "place an order," "cut corners" and "make a discovery," and the effects of instructions which direct learners' attention to input and to restrictions of combinations. Sixty Japanese students (30 intermediate, 30 advanced) took fill-in-the-blank tests followed by one session of instruction, involving a brief introduction to collocations and a discussion of common mistakes with collocations and differences in the collocational restrictions between English and Japanese. At home the subjects studied collocations using paper-based exercises provided after the pretest and/or online flashcards. Within two weeks after the pretest and instruction, the subjects came back to take a second fill-in-the blank test which served as the posttest. Statistical analyses show significant influences of various attributes, including overall frequency, literal vs. abstract meaning, the existence of L1 equivalents, and the presence of light vs. content verbs. The following eleven error types were identified: (1) Inappropriate paraphrases; (2) Misuse of light verbs; (3) Interference of the native language Japanese; (4) Blending two collocations with similar meaning; (5) Mistakes by using morphological synonymy; (6) Use of words other than verbs; (7) Inserting unnecessary articles, particles and prepositions between verbs and nouns; (8) Mistake in distinguishing intransitive and transitive verbs; (9) Creating collocations from compound nouns; (10) Misunderstanding actor-patient relations of verbs; and (11) Phonological errors. Among these error types, it was found that paraphrases, misuse of light verbs and interference of the native language are the strongest indicators of difficulty of collocations for the learners. Significant improvements were observed in the learners' performance in the posttest. These findings highlight the efficacy of improving second language learners' collocational knowledge to enhance their proficiency in the target language, and show that explicit instruction using learners' selective attention to input indeed improves their collocational competence in the target language. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]