A.during sleep.

　　B.in the endocrine glands.

　　C.under control of the nervous system.

　　D.during strenuous exercise.

　　4.The word “liberate” could best be replaced by which of the following?

　　A.Emancipate

　　B.Discharge

　　C.Surrender

　　D.Save

　　5.According to the passage another term for exocrine glands is___.

　　A.duct glands

　　B.endocrine glands

　　C.ductless glands

　　D.intestinal glands.

　　第六篇答案：BDCBA