BONUS VIDEO |– Origin of the Mutant Plural | Grammar | Khan Academy Video Lecture | Complete Course on English Grammar: Upgrade your Speaking & Listening - Personal Skills

hello grammarians I wanted to talk to
you again about mutant plurals so to
review a mutant plural is there are only
seven of them in English and they all
change sound when they pluralize you
don't add an S you don't add an en you
don't change the ending you change the
vowel and they're only seven to go like
this
there's man-woman tooth foot mouse louse
and goose and these words become in the
plural men women teeth feet mice lice
and geese now the reason that we have
these seven weird mutant plurals in
English is kind of complicated but I'm
lucky enough to be able to work with an
actual linguist hello Jake hey
grammarians Jake is it true that you are
a linguist yep it's true
all right so Jake what is the deal with
feet where where do these mutant plurals
come from if we take the word foot and
we drag it through history how do we get
how do we get to the plural as feet
what's the deal with that so if you look
at a lot of Germanic languages that are
around today you find similar words to
the word the English word foot in German
we have the word foots in Dutch we have
the word foote and when you have a lot
of different languages with slight
variations of a word it means there's
some old old word out there that all
these words are coming from so we can
pretty much be sure that there's some
proto-germanic word that sounds
something like food now back in those
days there was a different way to form
the plural and that was to add an e
sound at the end of a word so if the
word was food
then the plural was maybe foodie that
means many foots now there's a tendency
in language that you have to understand
here
it's called vowel harmony basically
means that vowels within a given word
they like to sound like each other so if
you have two syllables
those syllables will start to convey in
those syllables will start to converge
and in Germanic languages especially
there's there's one typical kind of
vowel harmony which okay now you have
two two vowels in a word the first vowel
will will try to sound more like the
second vowel if that second vowel is the
e sound just like in the plural
formation of nouns so you're saying that
the the suffix e at the end of this this
proposed word foo T the you sound tried
to sound more like the e sound this is
just a pattern that we found in Germanic
languages exactly it's very prevalent in
Germanic languages also exists in some
Romance languages some tiny Romance
languages so so what happens when you
combine the sound with the e sound what
sound do you get well strangely you get
the e sound I do sound what is what is
that the u sound are you okay
I think I'm okay you know we linguists
have to deal with this kind of thing all
the time we have very strong stomachs
mm-hmm you still get this sound in
languages like German and Dutch so then
that that's what this U is right so so
this sound or or I guess the so the
plural of German FUS is what you said
pizza so okay so so bring this home for
me so at some point in the development
of English or of all these Germanic
languages we had the foot we had this
word foot and then it turned into foot T
and then it turned into what and turn
into
fuchi something like Beauty right okay
now eventually that you sound dropped
out of English is why it's so hard for
us to pronounce and it was replaced in
pretty much all cases with the e sound
mm-hmm so we get the word
and then the e drops off and we're left
with foot as the singular and feet as
the plural cool so it goes from foot to
VT now that the same exact thing
happened with the word Mouse which
probably used to be moose because in
Frisian which is the closest cousin to
English the word for Mouse still is
moose moose and you find similar things
in a lot of Germanic languages like mesh
in Dutch and mouse in German the plural
became mu C and then eventually me see
then you get nice then during a few
hundred years later during the great
vowel shift that Mies becomes mice a lot
of evals in the great vowel shift five
hundred years ago became I've owls so
this is this is sort of the broad
pattern these these mutant words all
take is this umlaut mutation right
because this this this little these
double dots that go over a looks like a
smiley face that go over a vowel change
its color right the change its meaning
and that process is called either umlaut
mutation or i mutation not i like the
site organ i like the letter in English
cool well I hope that cleared some
things up for you you can learn anything
Dave it out Jake out that was a high
five got a slap