The teacher and writer___coming to___house.为什么前面要用Is而不是Are?

The teacher and writer___coming to___house.为什么前面要用Is而不是Are? what are the boy and girl doing 为什么girl前面不加the,为什么填are而不是is The writer and teacher is coing now为什么用 is 而不用are? 为什么要用is而不是are? The girl talking my teacher is my sister 为什么要用talking 可是它前面没 French fries are oily,and ice-cream are sweet.这里为什么用are而不是is when is the next plane for America America前面为什么用介词for而不是to? The police are duty on the duty on road.这里为什么用are 而不是用is? 为什么nine and one 是is ten而不是are the number of the workers here is about 50.句中为什么用is而不是are? the singer and the dancer（）come to Beijing.为什么要选have,而不是are呢 The fish are not fresh 为什么fish用are修饰而不是用is修饰