根据下面的短文内容，在短文后的空格处填上一个恰当的词，使短文完整、通顺。

Simon is my friend. He lives with  grandparents near a street in the city. His grandparents are very old. They can't walk very fast(快). The traffic is  in the street every day, so he is afraid (害怕) that the cars may hit(撞) his grandparents. He tells his father about this.

Simon's father says, "We  a farmhouse in the country, and your uncle lives there. There are not many cars there, and it is quiet in the country. Your grandparents can live there. I think they must be happy to  there."

Now Simon's grandparents live in the farmhouse with his uncle. Simon goes to see them with his parents  bus every week.