Here's some more stunning underwater footage. This time it's hammerhead sharks and stingrays, a wahoo and some striped eels, all filmed near the Cocos Island in the Caribbean. Take a look!

Alexander Pointer takes us through the conjugations of the verb "to be" in the present tense and explains how to form the contraction (otherwise known as the "short form") for each one.

In this episode, Doc Gruber and a colleague are testing a shark repellent. If effective, it could help save the lives of divers, swimmers and surfers all over the world.

Do you know your Turner from your Warhol? If not, don't worry, London is the perfect place to explore the art world through its wealth of museums. Watch and share Marcus's London story and let him take you on a journey of discovery. This Tate Modern curator is just one of the passionate staff waiting to introduce you to the people and ideas housed within the walls of the imposing former power station. Directly opposite St Paul's Cathedral across the Millennium Bridge, Tate Modern sits on the South Bank among one of the most vibrant new parts of the city.

The team's divers conclude their filming and come back to the surface unharmed. We learn more about current developments in the prevention of shark attacks.

Part Two of an exclusive journey through Middle-earth with the cast and crew of The Hobbit: An Unexpected Journey. Enjoy!

Nathalie and Jim get up close and personal with tiger and lemon sharks, trying to get the best footage while taking care not to disturb or excite the dangerous animals.

During this lesson, English teacher Alexander presents and explains different greetings in English and the time of day when each is used.

At times, Doc Gruber's research requires the team to dive right into shark-infested waters! Their line of work certainly isn't for the faint of heart! Enjoy.

Imagine having the chance to make the stars of stage and screen look perfect, and come face to face with the Royal family, every day. Watch and share Rebecca's London story as the colouring artist at Madame Tussauds London shares some of the behind the scenes secrets of her role, the traditional techniques used to create the ever-changing wax figures on show and the places she loves in London when she's not rubbing shoulders with the rich and famous.

Gruber's team of researchers work day and night. In this episode they record a shark's vital statistics while it's in a state of tonic immobility. Before releasing it, they take a DNA sample. Enjoy!

Miss World Megan Young's tour of London and her first thoughts as the New Miss World 2013!

Sam Gruber's team of biologists capture, tag and release a juvenile tiger shark. Then they track it electronically into the mangroves, an ideal location for their research.

Once more, the subject is "cover letter". In this second segment from Gabrielle, you'll hear some additional pointers and a brief summary of her advice at the end. Good luck!

Robby Naish talks about stand up paddle (SUP) wave riding and time spent on the Big Island of Hawaii with his crew "sessioning" different spots and enjoying surfing from sunrise to sunset.