题目

在密度和速度的大小比较中，正确的是（） A . 2.7t/m3比2.7g/cm3大 B . 2.7kg/dm3比2.7t/m3小 C . 0.2s/m比5m/s快 D . 1s/m与1m/s一样快 答案：D PART TWO  LANGUAGE KNOWLEDGE SECTION  A Directions: Beneath each of the following sentences there are 4 choices marked A,B,C and D. Choose the one answer that best completes the sentence(25%). 21. Perseverance is a kind of quality and that is ______ it takes to learn English well.      A. what                               B. that                          C. which                      D. How