Complex sentence: The only fresh troops available were the 1st/11th Sikhs, withdrawing from Pegu, and the 1st/10th Gurkha Riflesand a plan was prepared for them to attack the roadblock at 8.45 on the morning of the 8th, under artillery fire.
Split into simpler sentences: The only fresh troops available were the 1st/11th Sikhs, withdrawing from Pegu, and the 1st/10th Gurkha Rifles. A plan was prepared for them to attack the roadblock at 8.45 on the morning of the 8th, under artillery fire.