1. What if the avalanche happened?
要是发生雪崩怎么办？
还能这样说：
What can we do if the avalanche took place?
What if an avalanche came up?
谚语：
He who seize the right moment is the right man.
谁把握机会，谁就赢。
2. There is so little snow this year, so the sports association made snow with machine to create ski slope for the ski contest.
今年降雪少，因此运动协会人工降雪为此次滑雪比赛建造场地。
还能这样说：
The sports association founded a ski slope with a artificial snow for the ski competition, for it snowed little this year.
In order to found a ski slope for the ski match, the sports association made snow with machine, because there was little snow this year.
应用解析：
(as) white as snow 雪白，极白；
be snowed in (over) 被大雪封住；被花言巧语蒙蔽住
3. Learning skiing is as easy as shelling peas.
学滑雪轻而易举。
还能这样说：
It is a piece of cake to learn skiing.
Learning skiing has no sweat.
应用解析：
all of a sweat (=in a sweat) 满身大汗；焦急万分；非常害怕
4. Skiing is an exciting game.
滑雪是一项刺激的运动。
还能这样说：
It is very exciting to go skiing.
Going skiing is very exciting.
谚语：
A good book is a good friend.
好书如挚友。