---How do you deal with the disagreement between the company and the customers?
---The key ________ the problem is to meet the demand ________ by the customers．
| A．to solving; making | B．to solving; made |
| C．to solve; making | D．to solve; made |
_________, I could not memorize the text.
| A．However hard did I try | B．However hard I tried |
| C．However I tried hard | D．However I had tried hard |
The sons and daughters said they never fully appreciated their parents _________ it was too late to tell them.
| A．as | B．that |
| C．until | D．When |
Why not stay at home _________ the road is so slippery after the heavy snow?
A.since thatB. after that
B.then thatD. now that
Many people believe we are heading for environmental disaster _________ we basically change the way we live.
| A．but | B．although |
| C．unless | D．Once |
He is at least as tall as his brother, if not _________.
| A．tall | B．taller |
| C．so tall | D．the taller |