【判断题】Synchronized swimming is a hybrid of swimming, dance and gymnastics.
【简答题】亚油酸属于()脂肪酸。 (A)n-2系列 (B)n-3系列 (C)n-4系列 (D)n-6系列
【单选题】______ being fun and good exercise, swimming is a very useful skill.
【单选题】______ fun and good exercise, swimming is a very usefull skill.