Englishfor English speakers
each
Determinative
—
all or every one in a group separately
Come here you two. I'll give each of you a toy.
More and more problems happened each year.
We have to treat each individual case differently.
They each have good points and bad points.
Sara looked at each of the three bedrooms.
The price is $6 each.
one
Determinative
—
(ordinal first) The number 1.
We have one nose and one mouth.
one
Noun
—
The number 1.
One is the smallest whole number.
one
Pronoun
—
One is a singular pronoun which means "someone" or "people". It is used more often in formal writing.
It is easy to see the difference if one looks closely enough.
separately
Adverb
—
If you do something separately, you do it as individual .
We've been living separately for three years.