Yesterday，Mr．Green went to his hometown and visited the old house ____ he was born in．（ ）
A．whichB．whereC．whatD．it
You must make sure your mask （口罩） is clean you put it on．（ ）
A．beforeB．afterC．sinceD．where
We believe that China will become one of in the world．（ ）
A．the strong countries
B．the strongest country
C．the strongest countries
D．the strong country
Look at that girl! Is it Zhuoma？
No，It be her． Zhuoma has gone to her hometown．（ ）
A．mustn'tB．needn'tC．canD．can't．
I have never been to Beijing， Lisa．
．（ ）
A．Neither am IB．Neither I am
C．Neither have ID．Neither I have
Dr. Zhong Nanshan is a pioneer has made a lot of contributions （贡献） in the field of medical science．（ ）
A．whichB．whoC．whoseD．what