Motorcycling is a dangerous sport.是什么意思？

Motorcycling is a dangerous sport.

骑摩托车是一项危险的运动.

motorcycling

n. 摩托运动，[体]摩托车运动；

例句
The danger of motorcycling also helps account for many people's low opinion of the sport.
骑摩托车的危险也是许多人看不上这项运动的原因之一.

is

vt.& vi. 是（be的三单形式；n. 存在；

例句
Bollinger 'RD' is a rare, highly prized wine.
博林格RD香槟是一种名贵的备受推崇的葡萄酒。

dangerous

adj. 危险的；

例句
He's taking a dangerous drug: it acts very fast on the central nervous system...
他正在服用一种危险的药物：这种药物能很快影响到中枢神经系统。

sport

n. 运动，乐趣，老兄，变种；v. 嬉戏，得意地穿戴，故意显示；

例句
This is the most dangerous professional sport there is, and the worst paid.
这是最危险的职业体育运动，但报酬却是最低的。