It just bugs me (and does many other people, too) when I see writers confusing "loose" and "lose" when they should use the opposite word of the one they have written. For those of us who pay attention to such mistakes (and some of us just can't help ourselves), not only is the misuse of the words distracting, but we automatically tend to discount the writer's expertise (again, we can't seem to help ourselves, and do this discounting quite unconsciously). So what follows is an easy lesson in how to know when to use "loose" and "lose", so your loose use of grammar won't cause someone to lose their mind! I know that personally, when I see an article on "How to Loose Weight," what comes to mind is setting the weight free so it can find someone else (probably me) and stick to them, and with that image in my head, it's hard for me to imagine myself becoming thinner!

"Lose" should be used only for things you have had trouble finding or you do not want to find, or for not winning. "Lose the attitude, mister!" or "I'm going to lose my car keys if I don't put them away." The past tense is "lost". There is no adverbial form. Here are some common uses of the word:

To be unsuccessful in keeping possession of; misplace: I always lose my car keys.

To be deprived of (something one has had): lose your job.

To be unable to keep control or allegiance of: lose your patience; lose your fans.

To fail to win; fail in: lose a game, lose a contest.

To fail to use or take advantage of: lose an opportunity.

To rid oneself of: lose weight.

"Loose" is not an alternate spelling of "lose" but its own word. "Loose" is used for things that are not constrained: "Loose the dogs" means not to hide the dogs so you have to find them but to let them off the leash. The past tense is "loosed" (I know that might look strange to you but it is correct). The adverbial form is "loosely." Here are some common uses of the word:

Not fastened, restrained, or contained: a loose screw.

Not taut, tight fixed, or rigid: a loose tooth.

Free from confinement or imprisonment; unfettered: to let loose a dog.

Not tight-fitting or tightly fitted: loose clothing.

Not bound, bundled, stapled, or gathered together: loose papers.

Not compact or dense in its arrangement or its structure: loose packing.

Lacking a sense of restraint or responsibility; idle: loose morals.

Not formal; relaxed: a loose atmosphere at the cocktail party.

Not literal or exact: a loose translation.

Characterized by a free movement of fluids in the body: a loose cough.

And now for your easy reminder phrase: "My tooth is loose--if I'm not careful, I will lose it!"

I hope that these examples of the two words being used correctly have helped you to understand the difference between these words. Now that you know the difference between them, I hope you will remember how to use these two commonly confused words correctly, and not confuse either the words, or your readers!

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