He started to work dilligently _____ he came up with the idea of hybrid rice for the first time in the 1960’s.
| A．at once | B．the moment | C．for the moment | D．in no time |
The young man seized the thief by _________ collar and hit him on _________ head.
| A．the; the | B．his; his |
| C．the; his | D．his; the |
The seals _________ living fish.
| A．feed on | B．fed on |
| C．feed by | D．fed by |
Leaves gradually _________ around the fallen trunks.
| A．gathered | B．accumulated |
| C．collected | D．assembled |
—How was the debate last night?
— Super ！ Rarely _________ so much media attention.
| A．a debate attracted | B．did a debate attract |
| C．a debate did attract | D．attracted a debate |
Portia, for _________ physics had once been very hard, turned out to be a physicist.
| A．whom | B．whose |
| C．that | D．Which |