Complex sentence: On the morning of 27 June, Reinhold Messner was of the view that the weather would deteriorate rapidly, and set off alone from the last high-altitude camp started, but surprisingly his brother climbed after him and caught him up before the summit.
Split into simpler sentences: On the morning of 27 June, Reinhold Messner was of the view that the weather would deteriorate rapidly, and set off alone from the last high-altitude camp. Surprisingly his brother climbed after him and caught him up before the summit.