Acts of Kindness and Volunteerism Road Trip."可知，此次志愿者旅行活动的主要目的是传播善意和快乐。

　　2．How did people react to the "Smile！" signs later?

　　A．Disappointed. B．Worried.

　　C．Interested. D．Moved.

　　答案与解析：C　推理判断题。根据第二段的"Before long, some tourists wanted to take a photo with us and some strangers stopped to ask us about our signs."可知，后来，人们对标牌很感兴趣。

　　3．According to the last paragraph, why did the strange helper want to donate money?

　　A．Because he felt pity for the author.

　　B．Because he wanted to join in the project.

　　C．Because he hoped to help the homeless.

　　D．Because he felt sorry for his impoliteness.

　　答案与解析：B　细节理解题。根据最后一段的"'Please let me donate. It will make me feel like I'm a part of this adventure，'" he insisted.可知，这位男士是想参与到这项志愿活动中来。

　　4．What does the underlined word "astonished" in the last paragraph most probably mean?

　　A．Tired. B．Satisfied.

　　C．Frightened. D．Surprised.

　　答案与解析：D　词义猜测题。根据画线词后面的"It seemed as if he had known somehow."可知，作者他们一行人很"吃惊"，好像这位男士早知道他们需要80美元一样。

　　B

　　Many people like travelling, but they cannot take their dogs wherever they go. Some people let their dogs stay alone at home while others ask someone else to take care of their pets. If you're leaving your beloved pet at home for a holiday, it can turn into a bad experience. Luckily, you don't have to worry about your dogs anymore because Rover can cover for you while you are on leave. Rover is the latest service to offer at­home dog boarding. It's a good alternative (替代物) to boarding your dog at a dog boarding kennel (狗舍) or your neighbour's house.

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