04/22/2020
ASSURE or ENSURE or INSURE ...
The three words, assure, ensure, and insure, are often confused. All three words share an element of "making an outcome sure," and you can exchange these words with each other in some instances. However, rather than using these words interchangeably, we'd like to point out the unique aspects of each word so that you can use them to communicate your intention clearly, especially in American English.
Assure is to promise or say with confidence. It is more about saying than doing.
EXAMPLE: I assure you that you'll be warm enough.
Ensure is to do or have what is necessary for success.
EXAMPLE: These blankets ensure that you'll be warm enough.
Insure is to cover with an insurance policy.
EXAMPLE: I will insure my home with additional fire and flood policies.
Especially in American English, what you insure is a protective business transaction. What you ensure results from your personal efforts to make something happen. When you assure, you are promising a certain result to someone or something.
(... ref: The Grammar Book ...)
