Complex sentence: As Macdonough had predicted, British forces attempted to navigate the lake but because of unfavorable winds British commander Daniel Pring, whose forces were based at Isle Aux Noix in upper Lake Champlain, didn't complete the 65 mile journey to Otter Creek until May 14.
Split into simpler sentences: As Macdonough had predicted, British forces attempted to navigate the lake. Because of unfavorable winds, the British commander Daniel Pring, whose forces were based at Isle Aux Noix in upper Lake Champlain, didn't complete the 65 mile journey to Otter Creek until May 14.