I have tried to solve the problem, but it is so difficult that it ___ not only me but also my friend.
The way she thought of ____ money was to sell her hair.
Has all that ____ without delay ____ yet?
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? — ______.