难度一级 用时十分钟
nowadays,quite a few students are falling behind with their studies.there are many reasonsfor it. firstly,they lack confidence in themselves.secondly,some of them fail to devote themselves to their studies.wasting much time playing computer games. thirdly,some haven't formed good learning habits.for example,some are absent minded in class and some even don't go over lessons after class or finish their homework in time(上半部分)