請問PP Structure Test-1 28&73

由 **ereo** » 2006-01-20 22:28

28. Located at the upper end of each___ an adrenal gland, an integral part of the endocrine system.
答案是 kidney is
請問為什麼不行用 kidney which is?

73. Neptune circles the Sun once every 164.8 Earth years, and its day --- one rotation its axis--- is 15.8 hours.
爲什麼each 後面可以加years啊?
這個是對的，但不懂?

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