1. She is no enemy to mountain climbing.
她喜欢登山。
还能这样说：
She is fond of climbing.
She prefer climbing.
应用解析：
an enemy worthy of sb.'s steel 值得某人与之交锋的劲敌，强敌；
be an enemy to 厌恶；仇视；
go over to the enemy 投敌
2. He is an expert at mountain climbing.
他是登山专家。
还能这样说：
He is an expert mountainer.
He is an expert in climbing mountain.
应用解析：
climb over a fence 翻过围墙；
climb to power 上台；捞到大权；
on the climb 有迁升的希望；
climb aboard 上车
3. He spent the holiday indulging his passion for climbing.
他在度假期间尽情享受登山的乐趣。
还能这样说：
He enjoyed the pleasure of climbing during vacation.
He enjoyed the climbing to full during his trip.
应用解析：
indulge oneself in eating and drinking 纵情于吃喝；
indulge in tobacco 吸烟无度；
indulge in dream 爱空想
4. Now is the best season for climbing.
现在是登山的最佳季节。
还能这样说：
It is the best season to climb the mountains.
Climbing is at its best.
应用解析：
be seasoned to 适应；
season with 添加；
at seasons 不时地；
regular season 常规赛，倒行赛；
dull season 萧条季节，淡季；
flood season 汛期，洪水期