I must have been about fourteen then, and I put away the incident from my mind with the easy carelessness of youth．But the words, which Carl Walter spoke that day, came back to me years later, and ever since have been of great value to me．
Carl Waller was my piano teacher．During one of my lessons he asked how much practice I was doing．I said three or four hours a day．
"Do you often practice so long at a time?" asked my teacher．
"I try to," I answered．
Well, don' t," he said． “When you grow up, time won' t come in long periods．Practice in minutes whenever you can find them, five or ten before school, after lunch, or between household tasks．Spread the practice through the day, and piano-playing will become a part of your life．"
When I was teaching at Columbia, I wanted to write, but class periods, theme-reading and committee meetings filled my days and evenings．For two years I got practically nothing down on paper, and my excuse was that I had no time．Then I remembered what Carl Walter had said．
During the next week I conducted an experiment．Whenever I had five minutes to spare, I would sit down and write a hundred words or so．To my astonishment, at the end of the week I had a rather large manuscript （手稿） ready for revision, later on I wrote novels by the same means．
Though my teaching schedule had become heavier than ever, every day there were free moments which could be caught and put to use．I even took up piano-playing again, finding that the small intervals of the day provided enough time for both writing and piano practice．
There is an important trick in this time-using formula; you must get into your work quickly．If you have only five minutes for writing, you can't afford to waste four minutes chewing your pencil．You must make your mental preparations ahead of time, and focus on your task almost immediately when the time comes．Fortunately, rapid concentration is easier than most of us realize．
I admit I have never learnt how to let go easily at the end of the five or ten minutes．But life can be counted on to supply interruptions （中断时间）．Carl Walter has had a great influence on my life．To him, I owe the discovery that even very short periods of time add up to all useful hours I need, if I begin without delay．
Which of the following can be the best title of this passage?

A．Concentrate on Your Work	B．A Little at a Time
C．How I Became a Writer	D．My Teacher' s Advice

Which of the following statements is true?

A．The writer owes great thanks to his teacher for teaching him to work in long periods．

B．Carl Walter has had a great influence on the writer' s life since he became a student．

C．The writer didn't take the teacher' s words to heart at first．

D．Rapid concentration is actually more difficult than most people imagine．

The underlined part "counted on" in the last paragraph can be replaced by "____"．

A．enriched	B．concentrated
C．valued	D．expected

We can infer from the passage that the author ____．

A．has new books published each year however busy his teaching is

B．is always tired of interruptions in life because his teaching schedule is always heavy

C．has got into the bad habit of chewing a pencil while writing his novels

D．is devoted to work immediately because he can find enough time for preparations