A．to whichB．in whichC．by whichD．through which

A．at which

B．in which

C．on which

D．with which

A．to which

B．to whose

C．with whom

D．with whose

Which one is NOT the application of the system designed by Vaios Lappas？

A．To halt creating more space junk.

B．To remove the satellites at the end of their useful lives.

C．To stop the accidental collisions in space.

D．To clean the junk created by dead satellites.

A．to be based on

B．to base on

C．which to base on

D．on which to base

What is the main purpose of this passage？

A．To describe an experiment in which a Hydrapulper is used.

B．To introduce Hydrapulper, a new type of garbage disposer.

C．To tell what the writer thinks of the recycling of garbage.

D．To explain why garbage should be recycled in a new way.

I haven't decided which hotel______.

A．to slay

B．to stay at

C．is to stay at

D．is for staying

Which of the following is the purpose of the first paragraph？

A．To describe some successful doctors.

B．To compare poor writers with diseased people.

C．To tell the teachers why some 'students are poor in health.

D．To show the importance of a teacher's job.

Which of the following is the fourth step？

A．To question yourself.

B．To read for information.

C．To utter your answers.

D．To draw a conclusion.

I haven' t decided which hotel ______.

A．to stay

B．is to stay at

C．to stay at

D．is for staying