Lions，tigers and other animals are staying awake at night    1    （avoid）human beings，a new study finds．

Scientists have known that human activities can lead to changes in nature．Many animals may move around less or travel to far places to keep away    2    people．By being awake at night，animals can also be on guard against possible enemies and spend less time    3    （look）for food．

The latest research found even activities like farming and camping can    4    （fright）animals and cause them to become more active at night．    5    had been studied were lions in Tanzania，tigers in Nepal and monkeys in Brazil．Researchers compared    6    （careful）how much time those animals were active at night in areas of human activities，such as hunting and farming．    7    was human activities that caused an increase of about 20 percent in night time activities，even in creatures that usually sleep at night．Results    8    （publish）in the journal Science two months ago．

The new findings are    9    （usual）because no one else has looked at it in such detail before Ecologist Marlee Tucker was    10    （surprise）that any kind of human activities is enough for animals to see people as a threat．

2 . California is the third     1    (large) state and the most multicultural state in the US. This is not     2    (amaze) when you know the history of California,     3    has attracted people from nearly every country in the world. No one really     4    (know) when the first settlers arrived in    5     we now call as California. Historians believe that Native Americans reached California     6    means of a land bridge. In the 18^th century, California was ruled by Spain. Of the first Spanish to go to California, the majority were religious men. In 1848, due to the     7    (discover) of gold in California, the dream of becoming rich quickly attracted people from all over the world. In fact, few achieved their dream of becoming rich, but most remained in California to make     8    life for themselves. In more recent decades, California     9    (become) home to more people from Asia.     10     is believed that before long the integration of nationalities will be so great that there will be no distinct major racial or cultural groups.

3 . Are you facing a situation that looks impossible to fix?

In 1969,the pollution was terrible along the Cuyahoga River Cleveland, Ohio. It    1    (be) unimaginable that it could ever be cleaned up. The river was so polluted that it    2    (actual) caught fire and burned. Now, years later, this river is one of    3    most outstanding（杰出的）examples of environmental cleanup.

But the river wasn’t changed in a few days    4    even a few months. It took years of work     5    (reduce) the industrial pollution and clean the water. Finally, that hard work paid off and now the water in the river is    6    (clean) than ever.

Maybe you are facing an impossible situation. Maybe you have a habit    7    is driving your family crazy. Possibly you drink too much or don’t know how to control your credit card use. When you face such an impossible situation, don’t you want a quick fix and something to change immediately?

While there are    8    (amaze) stories of instant transformation, for most of us the    9    (change) are gradual and require a lot of effort and work, like cleaning up a polluted river. Just be     10    (patience).