They suggest making small changes like taking public transport, recycling, using low-flow shower heads, and buying light bulbs that use less energy. Even simple things like using     1     (recycle) paper or switching off the lights when you leave a room can help.     2     we add up all these small changes made by everyone worldwide, they won’t be such small changes. They could be the changes that save our future. After all, there is no substitute     3     our earth.

There is little doubt that Earth is getting warmer and warmer. In 2013, a lot of people     1     (shock) by a news photo of a dead polar bear     2     appeared to have starved and died. This alarming case showed how the increase in temperature had     3     effect on Earth’s ecology.

Climate scientists often mention a key climate process     4     (call) the “greenhouse effect”, which has two common meanings. Without the “natural” greenhouse effect, Earth could not sustain life. However, the “man-made” greenhouse effect has now become a big problem because more heat energy is trapped in the atmosphere, causing Earth’s surface temperature to rise     5     (quick).

There is strong evidence that the rise in temperature has led to an increase in extreme weather and natural disasters worldwide, not only     6     (cause) serious damage, but also costing human lives. Climate scientists have warned that if we do not take appropriate actions, this warming trend will probably continue and there will be a     7     (high) price to pay.

Governments need to consider making     8     (policy) and taking appropriate actions to reduce greenhouse gas emissions. We as individuals can also reduce our “carbon footprint”. It is our responsibility     9     (seize) every opportunity to educate everyone about global warming, along     10     its causes and impacts.

Earth Day is April 22.Every year, people carry out all kinds of    1    (active) in an effort to better the planet’s health.

One way to support this goal is    2     (grow)plants native to your area. This helps wildlife like birds and insects that evolved alongside native plants. For many of these animals, plant pollen(花粉)is their food.

Native pollinators(传粉者)often cannot recognize non-native plants food’s planting non-native species creates so-called“ food deserts” for pollinators including bees, birds, bats, butterflies and more. Doug Tallamy ,a professor, found that non-native plant species can harm the    3    (nature)food chain.

Humans depend strongly on insects.    4    them, we would have no flowering plants,     5    would harm the food web that supports important animals. Birds, for example, depend on plants for food and spread     6    (they) seeds while keeping the populations of harmful insects down.

Insects support plants that provide oxygen, clean our water, capture carbon and add nutrients to the soil. That     7    (build) topsoil and prevents flooding. Without insects, the biosphere-    8    living parts of the Earth-would rot because of the loss of insect decomposers(分解).Humans simply could not survive that，Tallamy said.

In addition to    9    (provide) food and habitat for insects and other wildlife, native plants are able to grow    10     (easy)and do not require much care. That means less watering and less fertilizing. The situation is a win-win for gardeners and pollinators.