重点、难点部分的教学是一节课的关键，教师的课堂教学的水平主要体现在重点的突出和难点的突破上。一般说来，一节课中学生要把握的主要知识就是本节课的教学重点，学生在理解和接受上存在困难的地方就是教学难点。
I have a grandpa, he is nearly 70 years old, it sounds old for him, but in his heart, he is really young. Two years ago, when I was in summer holiday, I went back to hometown and visited him. When I used my cellphone, my grandp...