For all its extremes, Venus is a（n) incalculable laboratory for researchers studying the weather and climate of earth.
A．invaluable
B．valuable
C．value
D．valueless

Section A
Directions: This section is to test your ability to understand short dialogues. There are 5 recorded dialogues in it. After each dialogue, there is a recorded question. The dialogues and the questions will be spoken only once. When you hear a question, you should decide on the correct answer from the 4 choices A , B, C, and D.
听力原文：W: John, what are you doing on your computer？ Don't you remember your promise？
M: Yes, I remember. I'm not playing games but typing my homework.
Q: What is the probable relationship between the two speakers？
（1)
A．Mother and son.
B．Teacher and student.
C．Husband and wife.
D．Boss and clerk.

Because this area has a high rate of crime and unemployment, there are only people moving out.
A．incentive
B．incident
C．incidence
D．initiative

Careful testing is necessary before any more experiments can continue with the exploring submarine.
A．needful
B．in need of
C．necessity
D．of necessity

__ we have finished the book, we shall start doing some exercises.
A．For now
B．Since that
C．Now that
D．Since already

听力原文：Unless the whole production cost could be reduced to a reasonable limit, the company would have to double its budget by next year.
（25)
A．The company's budget must be reduced reasonably next year.
B．The company's production cost is expected to rise next year.
C．The company has to stabilize its production cost.
D．The company is likely to go bankrupt because of its limited budget.