Is _______ necessary_______ the workers wear uniforms at work?A. it, for B. this, to C. it, that
Now things made by machine are cheaper than those made _____.
My cousin told me that he could eat three big apples _____.
You will realize what I have done for you _____.
As teenagers, we should study hard _____surf the Internet all day.
Please _____ your homework _____ before you hand it in.