They were the first to reach the 8,850-meter summit from the Nepalese side during this year's climbing season, which ends Tuesday, said Rajendra Pandey, a Mountaineering Department official.
At least two climbers have died in previous attempts this year, as strong winds and snowstorms have made climbing conditions miserable, forcing climbers to remain at the base camp for weeks.

　　Treacherous表示“变化莫测的；危险的或欺骗性的”，例如：treacherous waters（充满危险的水域）；treacherous weather（变化莫测的天气）；treacherous ice（看起来坚固而踏上去会破裂的冰）；a treacherous action（背叛行为）。