The most important thing about cotton in history is ______part that it played in _______Industrial Revolution.
| A．∕；∕ | B．the；∕ | C．the; the | D．a; the |
_______ he is always studying hard is well known ____ us all.
| A．How, to | B．What, to | C．That, to | D．Whether, by |
I believe ______ you have done your best and _____ things will improve .
| A．that.\ | B．\.\ | C．what, that | D．\.that |
What a pity ______is ________ you didn’t arrive by daylight.
| A．there, because | B．it, that | C．it, when | D．that ,for |
As the day was fine ，I made the suggestion _______ for a walk in the park .
| A．we go | B．we will go | C．should we go | D．that we go |
It is uncertain ______ the experiment is worth doing .
| A．where | B．that | C．whether | D．how |