完成句子。根据括号内汉语提示，完成句子。（6分）
小题1:It’s too dangerous to (游泳)__________alone.
小题2:Jack is the (高)__________of the five boys.
小题3:What would you do if your brother borrowed your bike without __________（允许）.
小题4:Sandy enjoys reading books and she has been to many (图书馆)__________.
小题5:Don’t forget to check your test paper (仔细)__________before the exam is over.
小题6:If you stand very close to the Europeans you are talking with,some might feel_________（不自然，不舒服）.
