1 . Human and their inventions, such as cars or plastic, have caused most environmental pollution on Earth. Today car emissions (排放物) are a major source of air pollution leading to climate change. In the meanwhile, plastics fill our ocean, creating a significant health issue to marine (海洋的) animals.

And what about the electric light, which is thought to be one of the greatest human inventions of all time? Electric light can be a beautiful thing, guiding us home when the sun goes down, keeping us safe and making our homes bright. However, like CO₂ emissions and plastic, too much of a good thing has started to influence the environment. Light pollution, the wrong use of outdoor light, is affecting human health, wildlife behavior and our ability to observe stars.

Light pollution is a global issue. This became obvious when the World Atlas of Artificial Night Sky Brightness, a computer-created map based on thousands of satellite photos, was published in 2016, which can be viewed online. The map shows how and where our globe is lit up at night. Vast areas of North America, Europe, the Middle East and Asia are glowing (发光) with light, while only the most distant regions on Earth (Greenland, Central African Republic and Niue) are in total darkness. Some of the most light-polluted countries in the world are Singapore, Qatar, and Kuwait.

Sky glow is the brightening of the night sky, mostly over cities, due to the electric lights of cars, streetlamps, offices, factories, outdoor advertising, and buildings, turning night into day for people who work and play long after sunset.

People living in cities with high levels of sky glow have a hard time seeing more than a handful of stars at night. Astronomers (宇航员) are particularly concerned with sky glow pollution as it reduces their ability to view stars.

Mostly over 80 percent of the world's population, and 99 percent of Americans and Europeans live under sky glow.

2 . My husband and I always wanted to go to the Caribbean but didn’t know much about the islands or how we were going to afford it. By chance, a friend of ours in Australia mentioned “pet sitting” and that it is something you can do all over the world.

We quickly created an account on a pet sitting website and began searching for options. There were only a couple of sits available in that part of the world, but we tried our luck, sent a request, and to our surprise, landed a three-month job in Grenada, so our year was going to be taken up with Caribbean pet sits.

Inspired by a Canadian couple, we decided to start our own travel blog. We began by writing about The British Virgin Islands, highlighting the beautiful beaches. However, for every photo album of a beautiful beach, there were 10 photos of trash (垃圾). It was hard to ignore the plastic pollution issue, especially on such primitive and remote beaches. So, we began to share photos of the trash we saw and how much we could pick upon our daily dog walks.

The more we looked into plastic pollution, the more we realized the severity of the global plastic pollution. From that point, we used our platform to create awareness and highlight ways to say no to plastic and travel plastic-free. We changed our daily routines, our way of living, and even our diets to accommodate more organic foods and little to no plastic packaging.

It’s been over three years now and we continue to do what we can. This journey has led us to some amazing places, working with great brands and even organizing a country-wide beach clean-up campaign in Grenada.

Our aim now is to keep on going. We love connecting with like-minded people. It’s been amazing few years that was sparked by a conversation about pet sitting. Who would have guessed?

Every year, more than 13 billion plastic bottles are sold in Britain. All of them     1     (use) only once, and only half of them are recycled.

Some think plastic bottles should be banned(明令禁止).     2     think they should be recycled. Others think a returning plan should be brought in to avoid the     3     (pollute) of rivers and seas. That is to say, people will get up to 20 pence back every time they return     4     bottle. A returning plan for bottles is already     5     (success) in Germany, where 98.5% of plastic bottles are returned.

    6     (lucky), there are already signs that things are changing for the better. Last year, Selfridges stopped     7     (sell) single-use water bottles. London Zoo announced that it would also ban them. It sold 155,000 plastic bottles of water last year. Now it will sell only reusable plastic bottles,     8     can be filled by visitors from taps. Families visiting beaches this summer are being asked to take part in a plan called “Return To Offender”. The idea is     9     (post) plastic bottles and other litter they find back to the     10     (company) that made them, using their freepost addresses.