2 Despite their popularity, the inherent nature of motorcycles makes riding them a potentially dangerous undertaking. (galyen.com)
Before airplanes and satellite phones, polar exploration was a more dangerous undertaking than it is now. (ldeo.columbia.edu)
And now an English woman called Judy Leden, female world champion in hang gliding and paragliding, has embarked on a fascinating yet highly dangerous undertaking. (tubitv.com)