Add punctuation: For the next three years he travelled frequently between England and the United States before accepting a temporary post at the University of Notre Dame in 1952
A: For the next three years he travelled frequently between England and the United States before accepting a temporary post at the University of Notre Dame in 1952.

Add punctuation: The changes in our surroundings and environment can also alter the impact of sex on aging individuals
A: The changes in our surroundings and environment can also alter the impact of sex on aging individuals.

Add punctuation: A Muslim must believe in Allah and the messengers Abraham David Joseph Jesus Moses
A:
A Muslim must believe in Allah and the messengers, Abraham, David, Joseph, Jesus, Moses.