IN: Which person is they?
The Saudi government beheaded eight Bangladeshis because they killed the Egyptian guard.
OUT: eight Bangladeshis

IN: Which person is she?
Alice helped Gwen move because she could not handle the job alone.
OUT: Gwen

IN: Which person is he?
Mr. Sanders gave James a promotion because he appreciated his good work.
OUT: Mr. Sanders

IN: Which person is they?
Blackberry alienated a lot of users because they were angered by the service being taken down for days.
OUT:
a lot of users