There: In or at that place. ex: The books go over there on the table.
Their: a form of the possessive case of they used as an attributive adjective, before a noun: their home; their rights as citizens; their departure for Rome.
They're: A contraction of they and are. They're a 100% correct. They're my favorite basketball team.
Where: in or at what pace?: Where is he? Where do you live?
Were: a 2nd person singular pt. indicative, plural past indicative, and past subjunctive of be. ex: Were you there last night? Where were they?
