A：开普勒揭示了行星的运动规律，奠定了天体力学的基础
B：法拉第通过实验研究，总结出法拉第电磁感应定律,为交流发电机出现奠定了基础。
C：洛伦兹预言了电磁波的存在，后来被赫兹用实验所证实。
D：安培通过多年的研究，发现了电流周围存在磁场，并提出了分子电流假说
青春是多彩的，又是矛盾的。下列不属于青春期矛盾主要表现的是（ ）
①独立性和依赖性的矛盾 ②自制性和冲动性的矛盾
③开放性和封闭性的矛盾 ④主动性和被动性的矛盾
制约西北地区农业生产的主要因素是（ ）
We have a big playground in our school .We all like to 1 games 2 after school .It's Friday .We have only two classes 3 the afternoon . 4 school is over（结束的）,a lot of students go to the playground quickly. The boys of Grade Two often 5 soccer. The girls like 6 them playing .Soccer is their favorite sport . Their teacher Mr Li also 7 football. Li Ming , Li Lei and Wei Fang are students of Grade One .They sometimes play 8 the students of Class Two. It’s half past five 9 . It's time 10dinner . My father is waiting for me at the school gate .
