Ⅱ. Vocabulary and Structure ( 15 points ) Directions : There are 15 incomplete sentences in this section. For each sentence there are four choices marked A, B, C and D. Choose one answer that best completes the sentence and blacken the corresponding letter on the Answer Sheet. 6. Jonathan and Joe left the house to go for__ after supper.
A、walk
B、the walk
C、wallks
D、a walk
40. Rescue dogs are chosen probably because__
A、they are loyal
B、they are brave
C、they have amazing appearances
D、they have good eyesight
52. What does the underlined word "centenarians" in Paragraph 1 refer to?