问题补充：
To me, the ocean is our greatest wilderness. I love swimming in it , surfing its waves, watching it from shore and thinking about all the life living unseen under the surface.
When I take my little kids to check out tide pools, we’re overjoyed when we find a sea star or some shellfish. Lately, though, Ive noticed a change in my favorite pools: there are more sea grasses and fewer animals with shells.
I can help feeling these small changes portend something more troubling about our oceans. It matches what scientists are telling us: our oceans are being troubled by carbon dioxide that threatens corals, colorful fish, salmon, sea otters, even whales. Our oceans are facing a major change.
Every hour, a million tons of carbon dioxide from cars, factories and power plants rain down on the world’s oceans. Carbon pollution brings about a chemical reaction that turns sea water more acidic (酸的) and takes away things important for sea animals .
Some of us are already feeling the effects of this growing crisis（危机）. Shellfish farmers in the Pacific Northwest have reported a decrease in natural and farmed oysters(牡蛎). Just this week, a new studyproved the link between the huge reduction in the numbers of oysters and ocean acidification. As polar waters become more acidic, Alaskan fishermen are troubled by the future of smaller fish.
Without action, ocean acidification will have a disastrous influence on the food chain, affecting not only sea life but the people who depend on it for food and their living. Already, our oceans have become 30 percent more acidic since preindustrial times, and it gets worse every day. We can stop this frightening dream, but only if we act now.
Thats why the Center for Biological Diversity has started a petition (请愿书) requesting President Obama and the Environmental Protection Agency to develop a plan to deal with ocean acidification. Decisive action can save sea life as we know it.
Now it isn’t too late to save our oceans and sea life. With immediate action to reduce carbon dioxide release we can start taking important steps today to deal with this disastrous situation. Join me in our petition calling for a national plan to save our oceans.
【小题1】The author’s recent visits to the tide pool brought her .A．happinessB．angerC．concernD．comfort【小题2】The underlined word “portend” in Paragraph 3 probably means .A．predictB．preventC．replaceD．reduce【小题3】What the author worries about most is .A．the harm of sea grassesB．carbon pollution in the seaC．that the petition may be turned downD．how fishermen can make a living in the future【小题4】What is the main purpose of the text ?A．To inform.B．To educate.C．To persuade .D．To instruct.C
答案：
(答案→)C
解析：文章介绍了作者对海洋碳污染的担心，号召读者开始行动，说服读者加入请愿书的行列。
【小题1】从第一段的句子：Lately, though, Ive noticed a change in my favorite pools: there are more sea grasses and fewer animals with shells.可知作者最近去池塘发现了担心的事情。选C
【小题2】从第二段的句子：可知这个单词是“预示”的意思。选A
【小题3】从第四段的句子：可知作者最担心的是海洋的二氧化碳污染。选B
【小题4】写作意图题：从最后一段的句子：Join me in our petition calling for a national plan to save our oceans.可知作者是在说服读者加入请愿书的行列。选C。
