Themissingboyswerelastseen________neartheriver.
A
所填的词为主语补足语，因其后有明确的地点，补足语表示动作当时正在进行中，所以只能使用 playing 。
Which of the folloing is NOT included in the fabled Five Mountains in China?
WhichofthefollowingisnotmentionedasWTO'sobjective?
TheWesternCouncilforTravelResearchin_______employedthetermvisitor.