Optimism is the art of always seeing the glass half full (1) half empty, finding something positive in even the most (2) of situations and last but not least the ability to expect the best even if the chances are (3) . It enables you to try new things, deal with failure as a learning experience (4) a stopping point. In general optimism gives you a reason to live. The world would be a better place if it was full of optimism, (5) unfortunately the trend in today’s youth is (6) the opposite way. Today it is (7) to be pessimistic. One could spend hours discussing how we arrived at this point, (8) our youth refuses to smell the roses and instead prefers to (9) themselves on their own pessimistic (10) .
Optimism is not an (11) gift but rather a learned behavior (12) . Like most behaviors optimism is best learned by watching examples, (13) you. The first step in creating a generation of people with a positive outlook on life, is to (14) life on the bright side yourself. (15) it would be wrong to (16) your child from all negativity, it is important that you are not the (17) of doubts and worries. Finding something positive in a negative situation needs to be (18) Show how to make the best of things by always (19) the positive, by encouraging your child after a(n) (20) and by explaining over and over that failure is just a part of progress.
17（）
A.origin
B.source
C.foundation
D.cause
参考答案：B
解析：
此句作者的含义是，我们不可能不让孩子接触负面的东西，但我们自己不应该成为负面东西的来源，也就是说，我们要注意自己的言行，自己对待事物要有乐观态度，避免孩子们受我们的影响。source“来源，源头”，如：He’s been a source of irritation or annoyance.“他使人生气，给人带来了烦恼。”根据句子的意思，应该选B。[A]origin侧重“(事物的)起源”，如：The social unrest has its origins in economic problems.“社会动荡是经济问题引起的”；[C] foundation意为“基础，根据”，如：The rumor was without foundation.“那条谣言毫无根据”；[D]cause“原因、理由”，用在句中意思正好相反。