---I didn't apologize to him for being unable to inform him of the change in the plan.
---But you________.
| A．ought to have |
| B．have to |
| C．should |
| D．must have |
He went out without an umbrella, ___________ in the rain.
| A．risked being caught | B．risking being caught |
| C．risked to be caught | D．risking to be caught |
Nowadays many pop stars begin to use recycled paper _________ plastic to package their photos.
| A．or rather | B．other than | C．rather than | D．more than |
Lily is said ________ abroad if his mother finds a job in the USA next year.
| A．to have studied | B．studying | C．to study | D．to be studying |
________ the question of how global warming has _________, we are doing some projects at school.
| A．Exploring, come about | B．To explore, come out |
| C．Having explored, come to | D．Being explored, come over |
Entering the room, they found that quantities of novels _________ on the desk, while a pile of illegal drugs were burned to _________ ground.
| A．Were, the | B．was, the | C．were, / | D．was, / |