Australia is unique in many ways. It's home to a wide range of landscapes and some of the most unusual animals on Earth. The Land Down Under is also the only place on Earth that qualifies as both a country and a continent. The definition of a continent isn't as concrete as you might expect, but a few qualities help earn Australia that distinction. 

The land mass's status (地位) as a country is for sure. A country is defined as "a nation with its own government, occupying a particular territory," and since 1901, the Commonwealth of Australia—as it's officially known—has fit that description. 

Australia's claim to be a continent is less strong. There's no scientific definition used to categorize continents. They tend to be large land masses with their own tectonic plates (地壳板块), and isolated enough to produce unique cultures and plant and animal populations. These aren't hard and fast rules, however. Europe and Asia share a tectonic plate, but their cultural differences justify separating them into two continents (though the boundary separating one from the other is constantly changing). When it comes to what makes Australia a continent, size is the most minor factor. It's the smallest continent at 2. 9 million square miles, and it's actually closer in size to Greenland than it is to South America. So what makes Australia a continent and Greenland an island?

Australia's distinctiveness carries a lot of weight here. Its isolated location allowed it to support native groups of people with distinct cultures as well as wildlife that can't be found elsewhere on the planet. The native cultures and animals of Greenland, however, can also be found throughout the Arctic.

On your busiest days, you may not be thinking much about what ends up on your plate. In fact, you may count yourself lucky if your meal doesn't come out of the convenience store. But abandoning your healthy eating goals can impede your health. After all, a diet rich in produce offers valuable nutrients not just to your body, but to your mental well-being.

But here's the irony. If you focus just on the mental and physical health benefits — instead of how delicious healthy foods can be — you may have a harder time getting those benefits, says a new study. "We are used to thinking about how nutritious foods will help our bodies, but these aren't our top priorities when we're hungry," says Brad Turnwald, study co-author from Stanford University. This can lead to a mindset that healthy eating is boring and even depriving(剥夺的). So to really use food to fuel your body and mind, it may help to try having delicious dishes that also happen to be nutritious.

Before you change your diet completely, Vagdevi Meunier, a professor at St. Edwards University, suggests making one change at a time. Instead of turning down both bread and fries at your next meal, she advises starting off by making just one swap, such as trading the fries for boiled broccoli, but letting yourself have a piece of bread. This will help your mind adapt to the changes instead of triggering（触发）your deprivation mode.

Eating food is not just about getting nutrients. Some elements such as a colorful feast for the eyes, and yes, good flavors are also important. Turnwald's study found that being mindful of these elements of eating could help you choose wisely. This could be as simple as topping a dish with some fresh herbs, or keeping a bottle of hot sauce at work to add the flavor of an otherwise "boring yet nutritious" meal. 

Planning your diet in advance is a research-backed strategy for keeping your desires in check. Researchers from Carnegie Mellon University found that people who decided on their lunch orders in the morning consumed five percent fewer calories than their colleagues who made their choices in the moment. By planning your lunch menu ahead of time — and planning something nutritious yet delicious — you'll get to eat what you want and your brain will benefit, too.

September is an exciting month in every college freshman's life. For many, i's the first time that they've lent home to live in a new environment. But after the hustle and bustle of a few weeks, excitement gives way to less enjoyable emotion homesickness.

Homesickness manifests itself in many ways. You may miss mum's coking your pet, or even your old bed. All this becomes a fond memory of the past. Homesickness can be a biter feeling for many students, especially when faced with the challenges of settling into an unfamiliar environment.

But remember, you're not alone. According to a recent BBC article, 70 percent of British college students experience homesickness. In this increasingly globalized world in which people migrate to faraway places for a relationship, education or work, homesickness is a feeling shared by many adults.

Homesickness can have similar symptoms to depression and in extreme cases it can develop into a panic attack. As for the term, homesickness or nostalgia wasn't invented until the 17^th century. It was considered a disorder by a Swiss physician, who attributed soldiers' mental and physical discomfort to their longing to return home, “nostos" from Greek, and the accompanying pain, “algos".

Studies in recent years, however, have shown that nostalgia may have some benefits to our mental health. After a decade of surveys and researches, Constantine Sedikides, a US social psychologist, found that nostalgia is what makes us human. He explains that nostalgia can resist loneliness, boredom and anxiety. Therefore, it's necessary for college students to learn some ways to overcome the uncomfortable feeling.