Put in the where necessary. Leave a OK if the sentence is already complete.
Who is *** Doctor Johnson? (The sentence is complete without the.)
Who is Doctor Johnson? (the/ok) OK
I was ill, so I went to see the doctor. (the/ok)
The President is the most powerful person in the United States. (the/ok)
President Kennedy was assassinated in 1963. OK
Do you know the Wilsons? They’re a very nice couple. (the/ok)
Do you know Professor Brown’s phone number? (the/ok) OK