Final answer:
The usual grace period for a semi-annual premium policy is 31 days, allowing extra time for policyholders to pay their premiums without risking policy cancellation.
Step-by-step explanation:
The grace period for a semi-annual premium policy is usually 31 days. This period is provided as a courtesy by insurance companies to allow policyholders extra time to pay their premiums without their policies lapsing. If a payment is not made by the end of the grace period, the insurance policy may be canceled due to non-payment. The grace period does not mean additional coverage; it simply allows more time for the policyholder to make the premium payment while keeping the policy active.