Questions 4 to 6 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions.
Now, listen to the conversation.
Questions 4 to 6 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions.
Now, listen to the conversation.Where is the man calling to

As one works with color in a practical, or experimental way, one is impressed by two apparently unrelated facts. Color as seen is a mobile, changeable thing (1) to a large extent on the relationship of the color (2) other colors (3) simultaneously. It is not (4) in its relation to the direct stimulus which (5) it. On the other hand, the properties of surfaces that give (6) to color do not seem to change greatly under a wide variety of illumination color, usually (but not always) looking much the same in artificial light as in daylight. Both of these effects seem to be (7) in large part to the mechanism of color (8) .

When the eye is (9) to a colored area, there is an immediate readjustment of the (10) of the eye to color in and around the area (11) . This readjustment does not promptly affect the color seen but usually does affect the next area to which the (12) is shifted. The longer the time of viewing, the higher the (13) , and the larger the area, the greater the effect will be (14) its persistence in the (15) viewing situation. As indicated by the work of Wright and Schouten, it appears that, at (16) for a first approximation, full adaptation takes place over (17) time if the adapting source is moderately bright and the eye has been in (18) darkness just previously. Also, (19) of the persistence of the effect if the eye is shifted around from one object to another, all of which are at similar brightness or have similar colors, the adaptation will tend to become (20) over the whole eye.

In general, the ancient Romans were a practical people. They cared less about philosophy anti pure mathematics than did the Greeks. The Romans were the best of the ancient engineers anti architects. They were brilliant students of Greek geometry and trigonometry, and they applied their knowledge to the constructions of fine bridges, roads, aqueducts, and public buildings.

They knew about the smelting of iron ore, but they used the iron they produced mainly for spears, swords, and shields, rather than for building construction.

While the Romans accomplished practical wonders, they did very little theoretical scientific thinking. Because of their frequent wars, many of their inventions were no more than improvements in the design of Greek weapons with which they were familiar.

There are two reasons for the Romans neglect of philosophy and pure mathematics. First, they were apparently too busy conquering nearby nations and forming them into a rapidly growing empire to waste much time on abstract thinking. Secondly, they were handicapped by the rigidity of their numerical system. The Romans did all of their arithmetic on an abacus, the ancient counterpart of the modem computing machine. Their number system discouraged the study of pure mathematics.

they got plague in the Middle Ages

they live in America, Asia and Africa now

men killed them all with diseases

brown rats took their place

正确

错误

正确

错误

He thinks it terrific.

He thinks the waiting is worthy.

He feels comfortable waiting so long.

He feels disgusted.