30. How long do you think it will be _____ we can find a new water source?
| A．after | B．before | C．when | D．Since |
With sufficient scientific information a manned trip to Mars should be _____.
| A．obtainable | B．potential | C．considerable | D．feasible |
_____ inviting guests and not treating them properly!
| A．Strangely | B．Fantastically |
| C．Surprisingly | D．Fancy |
_____ it is a good thing I did not get the post I had applied for, though I must admit that I was disappointed at the time.
| A．By the way | B．In a way | C．In the way | D．In no way |
The two things are the same in outward form but different _____.
| A．in addition | B．in brief | C．in common | D．in essence |
Despite their good service, most inns are less costly than hotels of _____ standards.
| A．equivalent | B．uniform | C．alike | D．likely |