Have you ever been in a meeting while someone was making a speech and realized suddenly that your mind was a million miles away? You probably felt sorry and decided to pay attention and never have daydreaming again. Most of us have been told from earliest school days that daydreaming is a waste of time. I don’t think so.
L. Giambra, a psychologist, says, “Daydreaming isn’t a waste of time. On the contrary , daydreaming is quite necessary. Without it, the mind couldn’t do all the thinking that it has to do during a normal day. You can’t possibly do all your thinking with a conscious（神志清醒的）mind. Instead, your unconscious mind is working out problems all the time. Daydreaming may be one way that the unconscious and conscious states（状态）of mind have silent conversations .”
Early psychologists paid no attention to the importance of daydreams or even thought they were harmful(有害的). At one time people thought that some psychological illness caused daydreaming. They did not have a better understanding of daydreams until the late 1980s. Eric Klinges, a professor, is the writer of the book Daydreaming. Klinges says, “We know now that daydreaming is one of the main ways that we organize our lives, learn from our experiences, and plan for our futures. Daydreams really are a window on the things that we are afraid and the things we long for (渴望) in life.”
Daydreams are usually very simple and direct, quite unlike sleep dreams. Sleep dreams may be hard to understand. It’s easier to get a deep understanding of your life by paying close attention to your daydreams than by trying to examine (分析)your sleep dreams carefully. Daydreams help you know the difficult situations in your life and found out a possible way of dealing with them.
Daydreams cannot be predicted: they move off in unexpected directions which may be creative and full of useful ideas. For many famous artists and scientists, daydreams were and are a main source(来源) of creative energy.
The passage is mainly about _______ .

A．winter sleeps	B．sleep dreams
C．daydreaming	D．predictions

The underlined phrase “On the contrary” means _________ in Chinese .

A．总之	B．相反
C．毕竟	D．因此

Psychologists now believe that ________.

A．daydreams cause some psychological illness

B．daydreams are usually difficult to understand

C．daydreams may be creative and full of useful ideas

D．daydreams are usually very simple and can be predicted

The writer quoted (引用) L. Giambra and Eric Klinges to ________.

A．list out two opposite ideas

B．point out the wrong ideas of early experts

C．support his own ideas

D．report the latest research on daydreaming