I caught the last bus from town, but Harry came home___________ that night.
| A．very late | B．even later | C．the same late | D．the last one |
The problem ________ this material can be used in our factory has been solved.
| A．that | B．what | C．whether | D．why |
The first thing ________ I did was to see if there were any products ________ might help me, but there only seemed to be powders ________ to kill snakes.
| A．that; /; designed | B．which; that; designed |
| C．/; that; designed | D．/; which; design |
________ is very important in doing any scientific work.
| A．Album | B．Category | C．Accuracy | D．Assume |
All efforts of cloning an animal will be ________ if there is not enough diversity in the group to overcome illness.
| A．in need | B．in place | C．in vain | D．in case |
It was the building of the rail network from the west to the east coast ________ brought even larger numbers to California in the 1860s.
| A．that | B．what | C．how | D．which |