Due to the widespread ____ of advanced technology, the price of computers has come down greatly.
Has all that ____ without delay ____ yet?
I don’t think he could have done such a stupid thing last night, _____?
A man may usually be known by the books he reads _____ by the friends he keeps.
Although he is often tired _____ his work, he is never tired _____ his job. In fact, he enjoys it.
— Is your mother still a teacher? — ______.