By isolating those circuits using generator power, a transfer switch eliminates the risk of backfeeding the electrical utility which can cause injury to utility workers and property damage.
(a transfer switch; eliminates; the risk of backfeeding the electrical utility) (the electrical utility; can cause; injury; to utility workers and property damage)
a transfer switch the electrical utility
eliminates can cause
the risk of backfeeding the electrical utility
injury to utility workers and property damage