Tian Gong I was successfully launched ___ September 29th, 2011 ____ Jiuquan,Gansu province.
A.in;on B.on;in C.on;on D.in;in正确答案B
Tian Gong I was successfully launched ___ September 29th, 2011 ____ Jiuquan,Gansu province.
A.in;on B.on;in C.on;on D.in;in正确答案B