按要求转换句型，每空一词：

　　They are having open classes.(改为单数)

　　He is having ________ open ________.

就画线部分提问：

　　This sweater is twenty yuan.

　　________ ________ is this sweater?

就画线部分提问：

　　Mr Li's room is next to him.

　　________ ________ is next to him?

就画线部分提问：

　　I have been to Beijing twice.

　　________ ________ ________ ________you been to Beijing?

就画线部分提问：

　　It's cloudy and windy today.

　　________ the ________ ________ today?

就画线部分提问：

　　Wei Hua was late for school because her mother was ill.

　　________ ________ Wei Hua late for school?

就画线部分提问：

　　My mother is an English teacher.

　　________ ________ your mother?

就画线部分提问：

　　The girl will get everything ready in twenty minutes.

　　________ ________ will the girl get everything ready?

就画线部分提问：

　　She has to go there on foot every three days.

　　________ ________ ________ she have to go there on foot?

就画线部分提问：

　　This suit costs 338 dollars.

　　________ ________ ________ this suit cost?