34. This is____ a difficult problem ____ all of us can't work it out.
—Sorry, sir.He ____to a meeting soon.
The research showed beyond that smoking contributes to heart disease.
That art center is ____ used to be a factory,_____ millions of cars were made.
—Are you going to help him? —Why ___ I help him? He' s never done anything for me.
The captain determined to be with the ship forever and never to disappointment even when the ship sank.