contractions and apostrophes
The mark that stands in for omitted letters.
Put the apostrophe where the letters dropped out: don’t, can’t, it’s, they’re. Won’t is irregular. Contractions are standard English. They are not required. Do not use the apostrophe to make a plural.
Examples
UseIt’s ready.
UseThey’re ready.
AvoidIts ready.
Avoidthe 1990’s