The professor could tell by the _________look in Mars's eyes that she didn’t understand a single word of his lecture.
| A．cold | B．blank |
| C．fresh | D．innocent |
Stephen Hawking believes that the earth is unlikely to be the only planet______ life has developed gradually.
| A．that | B．where | C．which | D．whose |
The lawyer listened with full attention, ______to miss any point.
| A．not trying | B．to try not | C．trying not | D．not to try |
That is the only way we can imagine______ the overuse of water in students’ bathroom.
| A．to reduce | B．reducing | C．reduced | D．reduce |
—Peter, where did you guys go for the summer vacation?
—We ______busy with our work for months, so we went to the beach to relax ourselves.
| A．were | B．have been | C．had been | D．will be busy |
Many buildings in the city need repairing, but the one ______first is the library.
| A．repaired | B．being repaired | C．repairing | D．to be repaired |