Pluto, the outermost planet of the solar system, _____photographically in March 1930.
A: discovered
B: was discovered
C: by discovery
D: when discovered
A: discovered
B: was discovered
C: by discovery
D: when discovered
举一反三
- Pluto, the outermost planet of the solar system, ( ) photographically in March 1930. Pluto, the outermost planet of the solar system, ( ) photographically in March 1930.
- He became very friendly when he ____________ that she was my sister. A: was discovered B: discovers C: has discovered D: discovered
- It ______ long ago that the earth is round. A: was discovered B: is discovered C: discovers D: discovered
- Madame Curie is believed ____ the radium. A: discovering B: having<br/>discovered C: to have discovered D: to discovered
- While building a tunnel through the mountain, ________. A: an underground lake was discovered B: there was an underground lake discovered C: a lake was discovered underground D: the workers discovered an underground lake