题目内容：

Wang Kun and Wang Wei are brother and sister. They have dreamed of _1.______ (take) a great bike trip. It was Wang Wei ___2.___ first had the idea to cycle along the Mekong River. They rode bicycles to travel __3.___ the Mekong River, ___4.__ source is in Qinghai Province. __5.___ it enters Southeast Asia, it travels slowly through hills and low valleys and the plains where rive grows. Despite ___6.__ difficulties, Wang Kun and Wang Wei were __7.____ (determine) to begin their journey at an altitude of more than 5000 ___8.____(meter) in Qinghai Province. During their journey, they __9.____ (enjoy) the continuing change of the weather. Finally, they reached Dali in Yunnan Province, Dao Wei and Yu Hang joined them. The four of ___10.___ went on with their great bike trip.