cho tam giác ABC . Gọi M là trung điểm của BC. trên tia đối của tia MA lấy điểm D sao cho MA=MD. 
a) Chứng minh tam giác ABM=tam giác DCM và AB///DC
b) Kẻ BE vuông góc với AM( E thuộc AM ), CF vuông góc với DM( F thuộc DM ). Chứng minh: M là trung điểm của EF

Rewrite the following sentences, using the given words and beginnings.
  1. You are active, and your brother is active too =>
     You .................
2. We all find painting interesting because it's a creative actibity
=> We all think ................................
3. My sister doesn't like reading books
=> My sister hates .....................
4. Many people think that birdwatching is boring 
=> Many people find.......................
5. Hoa's father likes collecting coins 
=> Hoa's father is .....................
6. My brother's hobby is playing the guitar
=> My brother loves .....................
7. He is clever. He is active
=> He is clever and......................
8. Jenny doesn't eat much not to be overweight
=> Jenny doesn't want to be overweight, so she.......................
9. He likes collecting coins in his free time
=> His hobby ............................