中国大学MOOC: How many chidren do Niulang and Zhinv have?
                    举一反三
- 中国大学MOOC: What separated Niulang and Zhinv in the folk tale?
 - 中国大学MOOC: How many types of booth do we usually have ?
 - I don't know ________________. A: how many children he has B: how many chidren does he have
 - 中国大学MOOC: What animal helped Niulang and Zhinv reunite once a year according to the folk tale?
 - What separated Niulang and Zhinv in the folk tale?
 
