题型:问答题 简答题 This is the very mountain I mentioned in the letter, __________the top is covered with snow all the year round. [ ]A. whoseB. of which C. its D. that 查看答案
题型:问答题 简答题 For all its extremes, Venus is a(n) incalculable laboratory for researchers studying the weather and climate of earth.A.invaluableB.valuableC.valueD.valueless 查看答案