题目

下列是一元一次方程的是（） A . x-3y=3 B . x2-3x=3 C . -3x=3 D . x-1= 答案：C— Excuse me, could you tell me        ?— Certainly. In half an hour.A．when the high speed train would arriveB．when the high speed train will arrive C．when would the high speed train arriveD．when will the high speed train arrive