Why here is an interjection, placed at the beginning of a sentence to express surprise:Is it nine o'clock already?Why, i must have fallen asleep!Are you suggesting he stole the money?I don't know why, but it seems to me that bob would sound a bit strange if he said, why is it that you have to get going? in that situation.Good explanation of why it's optional in this case, although i'm not convinced that reason is the only reasonable antecedent of why.For example, the explanation why is a common usage, and i don't …
What happened to Joy Reid? 'The ReidOut’ canceled on MSNBC; here's why
What happened to Joy Reid? 'The ReidOut’ canceled on MSNBC; here's why

What happened to Joy Reid? 'The ReidOut’ canceled on MSNBC; here's why of Why Is Joy Reid Leaving MSNBC? Did She Just EXPOSE Someone? .

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Thus we say:You never know, which is why but you never know.That is why and goes on to explain:There is a subtle but important difference between the use of that and which in a sentence, …