Indefinite pronouns are words like someone and anything that people use to talk about people, things, places, and so on when they don't know or don't want to say the actual name. Most languages have some words to express these concepts, but they often don't translate perfectly from one language to another.
Mi'gmaq has several different groups of indefinite pronouns. They are all based off the question words: wen 'who', goqwei 'what', tami 'where', tal 'how', etc.
wen telim'sg's? person told.you
'who told you? (expect the name of a person as response)'
 By themselves
Sometimes a question word can appear by itself as an indefinite pronoun, for example. You can tell the difference between wen meaning 'anyone/someone' and wen meaning 'who' because when it means 'who' it will be at the beginning of the sentence, as shown above, and when it means 'anybody/somebody' it will be somewhere later in the sentence, as shown below.
telim'sg's wen? told.you person
'did anyone/someone tell you? (expect response e'e 'yes' or moqwa 'no')'
The same pattern works for the other question words and indefinite pronouns.
'do you see something/anything?'
'what do you see?'
'are you going somewhere/anywhere?'
'where are you going?'
The indefinite pronouns that look just like question words can also be used in sentences that aren't questions at all. For example, sentences about conditions (often translated with 'if' in English):
nemij wen, tlimitis if.you.see person, you.will.tell.me
'if you see anyone/someone, you will tell me'
You can also see this type of indefinite pronoun with mu 'not', where it is always translated as any(one, body, thing, etc) in English.
mu teluwewap nemiaqap wen not I.said.neg I.saw.neg person
'I didn't say I saw anyone'
Sometimes when mu is right before wen or goqwei, it sounds a little different and is written mo, but the meaning is the same whether they are together (first example below) or separated by the verb (second example below).
mo wen pegisinug'p not person arrived.neg
'no one arrived'
mu pegisinug'p wen not arrived.neg person
'no one arrived'
When the sentence is in the future, mu changes to ma (see also Future). This happens exactly the same way when there is a wen.
ma wen 'pgsinug not.fut person will.arrive.neg
'no one will arrive'
The second group of indefinite pronouns is formed by adding nat- or nata- in front of any word from the first group. These are generally written as all one word.
nata-wen pegising'p indef-person arrived
'someone arrived '
nata-wen nutaqap indef-person I.heard
'I heard someone'
amujpa nata-wen piluwei pipanimatis have.to indef-person else you.will.ask
'you'll have to ask someone else'
These nata- words include natawen, natgoqwei, natami, natal, and so on. These words are often translated into English as 'someone/somebody', 'something', 'somewhere', 'somehow', respectively. However, you can't use a nata- word in all the places where you can use a some- word. Notice that in the examples with natawen above, it wouldn't make sense to translate these sentences using 'anyone' (*anyone arrived, *I heard anyone, *you'll have to ask anyone else). They only sound okay with 'someone' (or 'somebody'). However, in the examples with wen above, both 'anyone' and 'someone' sounded fine as translations, and meant the same thing (did anyone/someone tell you?, if you see anyone/someone, tell me). The only time when we can't translate wen with both 'someone' and 'anyone' is when it is with mu 'not', but this is pretty easy to recognize.
So to sum up, we use just wen/goqwei/etc. when you can translate the sentence with 'anyone/anything'/etc and 'someone/something'/etc, and get the same meaning, or when there's a mu so our translation would be 'not...anyone/no one'. We use nata- with wen/goqwei/etc. when the only reasonable translation is with 'some-'.
There is one last main group of indefinite pronouns, and these are used when the only reasonable translation is with 'any' but there isn't a negative mu. They are made up of the word tampas plus the same wen/goqwei/tami/tal/etc as the other groups. Unlike nata-, tampas is conventionally written as a separate word, so we have tampas wen, tampas goqwei, tampas tami, and so on.
Ma'li me misgilg aq tampas wen Mary more big than indef person
'Mary is bigger than anybody (else)'
gis tlimatis tampas wen able.to you.tell indef person
'you may tell anyone'
gelug'p tampas wen I.talked.to indef person
'I talked to anyone, any old person'
There are also some cases with ta'n plus wen/goqweietc, which seem to be able to be translated with both 'some-' and 'any-', but is not completely identical to these words without ta'n. I'm not quite sure how exactly this group works yet, but here is an example.
mu teltet'mu eig ta'n-wen getoq not I.think.neg there.is indef-person knows.it
'I don't think that there is someone who knows it, I don't think that anyone knows it'