句型转换。
1. Vera is fourteen years old.(对画线部分提问)
     __________ __________ is Vera?
2. I was born in 1973. (对画线部分提问)
     __________ __________ you born?
3. They have a pop concert every year.(改为一般疑问句)
      __________ they__________ a pop concert every year?
4. How old are you?(改为同义句)
    What's__________ __________?
5.You are welcome.(改为同义句)
    That's__________ __________.