根据短文内容和首字母提示，在下文空格处填入适当的词使短文完善（每空一词）
Frank was a curious boy. The first time he saw an hourglass(沙漏),he wondered what it was.
His mother said,”An hourglass is made in the s ____ of 8. The sand is put in at one end,and runs through a small hole in the m ____ . It takes the sand exactly an hour to run through.”
Frank w ____ the little stream of sand. He was i ____ ,because it would not run faster. ‘Let me shake it,mother,”said he,”it is lazy,and will never get through.”
“It will,Son,”said his mother, “The sand moves little by little,but it moves all the time. When you look at the hands of the clock, you think they go very s ____ , but they never stop. While you are at play,the sand is r ____ , grain by grain. The hands of the clock are moving,second by second. At night,the sand in the hourglass has run through twelve times. The hour hand of the clock has moved a ____ its great face. That is because they keep working every minute. They do not stop to t ____ how much they have to do and how long it will take them to do it.”
Now, Frank’s mother wanted him to learn a little poem,but he said,‘Mother,I can never learn i ____ ,”His mother said,”Study all the time.N ____ stop to ask how long it will take to learn it.”
Frank followed his mother’s advice. He studied line after line,very busily; and in one and a half hours he knew the poem perfectly.
中，
，
，
，那么角
等于（ ）
