单项选择题
Human behavior is mostly a product of learning（）the behavior of animals depends mainly on instinct.
A.so B.unless C.if D.while
单项选择题 She got a job as an assistant stage manager at the Cambridge Arts Festival Theatre, thinking that it might（）to a career as a playwright (剧作家).
单项选择题 （）the've got to know each other a little better, they get along just fine.
单项选择题 （）,John has been to several foreign countries.
