I've worked with teenagers for five years. I've spent time (1) ___________ to them besides teaching them English. I remember once I asked them (2) _________ their parents or classmates had more influence on their success at school. Some said their parents had greatest influence on their achievement. The reason given was that parents usually loved their children unconditionally, and they definitely would (3) _______ their best to help and support their children. For example, parents could do all housework so that their children could have time for studying. (4) ________, some students revealed that their parents were too busy to spend time with them. Therefore, it was difficult for parents to help their children. In this case, classmates or friends affected their success most (5) ______ they talked to them more and they helped each other to deal with any difficulty in studying. 1. A. talk B. talking C. to talk D. how to talk 2. A. what B. which C. whether D. that 3. A. try B. make C. take D. work 4. A. Moreover B. Therefore C. However D. Unless 5. A. since B. as C. because D. although