Finding a mask which offers you a high protection level is crucial to filtering(过滤) out any particles for a long time. However, after a few hours, the mask becomes contaminated(污染) by the particles and you need to replace it with a new one. See, you have to get a mask offering active protection in addition to passive filtration.

The first rule of a mask offering you any kind of protection is that it needs to fit well. The mask also needs to be comfortable and allow you to breathe easily for you to be able to keep it on for as many hours as you need.

During long hours of wear, food and dirt may remain on the inside of your mask. All the hours spent in a place with less-than-ideal conditions for human health are wonderful news for bacteria that thrive on food particles and muck left behind on the inside of your mask. This growth opportunity for bacteria could not just be dangerous but could also cause a bad smell. So you'd better have a kind that kills off the smell-causing bacteria, leaving your mask smelling fresh.

You should look for cloth masks that have multiple layers of breathable fabric that is tightly woven, include a robust(结实的) nose wire for you to adjust the mask to the shape of your face and prevent air escaping from around your nose, do not have gaps around the nose or sides of the face and that block out the light if you hold the mask up to a bright light source. It is good for the mask to come with your choice of either head straps or ear straps, both adjustable. It is also good if the mask has different sizes ranging from kids to adults to ensure everyone stays protected.

Technology is developing by leaps and bounds. A small device such as a smartphone now has more processing power than rockets to the Moon once had. New tech brings many advantages, making our lives easier and opening up new opportunities. One piece of kit that's been really taking off recently is the drone. This pilotless mini aircraft, originally developed for aerial (航空的) photography and warfare，is now bringing us benefits closer to home. In the last few years, tech companies such as Amazon, Alphabet and Uber have promised us delivery drones-bringing goods to our doorsteps in a matter of minutes. While progress in developing them has been slow, drones are becoming more and more involved in our life.

Drones are helping to connect with and enhance the lives of people in remote locations. In the UK, the Royal Mail wants a fleet of 500 drones to help deliver the mail to faraway communities. Windracers, the company developing the drones, say theycan ny in fog and produce 30% fewer emissions than comparable piloted aircraft. And in Coventry in the UK, construction has started on an air center, which will act as a base for police and delivery drones. Urban-Air Port Limited is working with car-maker Hyundai on the mini-airport, known as a skyport.

Drones can also play a part in improving the health of millions of people. For example, an incredible development project by the University of South Australia is for drones to eventually be able to survey populations for disease by reading the blood oxygen levels of humans from the air. They'll also be able to scan for other vital signs, like coughing and a high temperature.

It seems that the sky is the limit for what drone technology can achieve. The only thing that sometimes keeps it from working is regulation. Writing for the BBC, Jessica Brown says: "If our skies are to become as crowded as our streets, airspace rules need updating to prevent accidents."

For a long time, geologists have been fascinated by a missing piece of Earth's history-a lost continent called Argoland. Around 155 million years ago, the 5,000-kilometer continent broke off from Western Australia and began drifting (漂) , leaving behind a basin deep below the ocean known as the Argo Abyssal Plain.

But where did Argoland actually go? 

The seabed structure suggests that the continent drifted northwestward and ended up Southeast Asia. But surprisingly, there is no large continent hidden beneath those islands, only small continental fragments (碎片) surrounded by ancient oceanic basins. Using this theory, geologists at Utrecht University discovered that Argoland hadn't really disappeared but survived as a "very extended and fragmented collection" under the islands to the east of Indonesia.

Unlike other continents like Africa and South America, which broke neatly into two pieces, Argoland split into many smaller fragments that were dispersed, which made it difficult for scientists to locate and study the continent's geological features. However, with advanced technology and the discovery, scientists can now piece them together.

Tracking the continents is vital for understanding processes like the evolution of biodiversity. It could help explain something known as the mysterious Wallace line, which is an imaginary boundary that separates mammals, birds, and even early human species in Southeast Asian islands. The boundary has puzzled scientists because of how clearly it separates the island's wildlife. To the west of the line are placental mammals like apes and elephants. But these are almost completely absent to the east, where you can find marsupials and cockatoos—animals typically associated with Australia. Researchers have theorized that this may be because Argoland carried its own wildlife away from Australia before it crashed into Southeast Asia, which helps explain why different species are found in different nations.

The story of Argoland is not one of complete disappearance but of transformation. As the world continues to evolve, this lost continent serves as a powerful symbol of the fragility of life on this planet, and a reminder of the importance of respecting and protecting the world that we live in.