For example, I can say "used for storing fat", or "used to store fat". What is the difference between the two phrases?

  • store fat what's that? :O
    – Maulik V
    Dec 6, 2014 at 5:08
  • A tissue of human body can store fat.
    – Rui
    Dec 6, 2014 at 5:37
  • True..but context was important. It's better to mention that or else you may not get a proper answer or others may simply put this question 'close'. Just a good practice to follow as I see here.
    – Maulik V
    Dec 6, 2014 at 5:39

1 Answer 1


These two sentences:

The lizard's tail is used to store fat.

The lizard's tail is used for storing fat.

mean exactly the same thing. The s in used is pronounced soft, like a z. In IPA, that's /juzd/.

An auxiliary verb

Used to can also work as an auxiliary verb indicating the "imperfective aspect" or "past tense with habitual aspect", like this:

The lizard used to store fat in its tail, before the mad scientist altered its metabolism.

or more realistically:

Mom used to bake cakes all the time, before she gave up eating sugar.

Your jokes used to be funny.

Many people pronounce the s hard (unvoiced) in this sense of used to, resulting in this pronunciation: /just tu/ or even /jus tu/. Used for cannot be used in this sense.

A synonym for accustomed to

Used to also can mean the same as "accustomed to", as in these sentences:

My mom's cakes taste terrible at first, but you'll get used to them.

The lizard is used to living in a cage.

Many people also pronounce this sense of used to /just tu/ or /jus tu/. Used for does not have this sense, either.

  • So they are basically the same, except for the last two uses.
    – Rui
    Dec 6, 2014 at 5:40
  • 1
    Also be mindful of The lizard's tail is a vestigial organ. It used to store fat. In this case, used to modifies store, and indicates that the fat-storing function of the tail has ceased.
    – Adam
    Dec 6, 2014 at 15:28
  • @Adam Indeed that's more plausible than my mad-scientist example.
    – Ben Kovitz
    Dec 6, 2014 at 15:30
  • How about The lizard used to store fat it its tail, before Monsanto modified its DNA to store fat in saffron flavored lumps on its back. Paella on the cheap!
    – Adam
    Dec 6, 2014 at 15:34
  • The last "used" there is an adjective - not to be confused with the verb, or compared to it - (it is famous for causing problems for students). Nice pron points Dec 6, 2014 at 19:10

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .