Commence and commerce are easily confused words.
The spell-check application of most word processing software programs would not catch a slip-up of these two words. Spell-check is looking for words that aren’t in its dictionary, and words that resemble words in its dictionary but are possibly spelled wrong. Spell-check isn’t perfect. It doesn’t know and can’t guess what word you wanted or what word you meant, it can only judge the words on the page. If you used words that are all spelled correctly, it gives you a pass anyway.
Autocorrect suggests words that start with the same letters. It’s suggesting what word you may want to save time, but quite often, its suggestions are pretty off base. They don’t help you out, but they do make you laugh.
Commerce is a noun. It is another way of saying making a exchange or doing business. It’s often used to refer to the business world’s activity as a whole, whether domestically or internationally.
Commence is a verb. It means to bring an event to an end, or a school year to a close. Maybe you’ve heard graduation ceremonies called “commencements.” That’s the noun form of this word.
The following story uses both words correctly:
During an election season, right wing candidates are dismissive of commerce regulations of any kind. Their reasoning is most business transactions would abruptly commence, and the economy would grind to a halt. “The invisible hand of the marketplace is the only regulation we need” is a frequent refrain for their side.