We are going to Beijing by plane.
We are going to Beijing by air.
We are going to Beijing by airplane.
这三个句子都符合要求,意思也都一样,都行.要填五个单词啊We are going to go to Beijing by plane.We are going to go to Beijing by air.We are going to go to Beijing by airplane.是这样吗？还可以用We are going to take the plane to Beijing.我觉得这个可能更符合标准答案吧。