____ met, it won't be easily forgotten.
A: If only
B: When if
C: Once
D: Once you were
A: If only
B: When if
C: Once
D: Once you were
举一反三
- From the conversation we know that David and Bruce ______. A: have met only once B: have never seen each other before C: once worked in the same office D: were once business partners
- When he was a solider abroad, Edward would always contact his family through telephone calls, but usually ________________. A: only about once a month B: only about once a year C: only about once a week D: only about once a day
- The instructor won"t give them any help ______ absolutely necessary. A: when B: if C: unless D: once
- ________, you must continue. A: Once you begin B: When you begin C: Once you will begin D: While you begin
- _________ that the earth was the center of the universe. A: People were once believed B: It had once believed C: People were believing D: It was once believed