A few years ago，I stood in a small classroom just outside of New York City，watching a high schooler named Serena Stevenson answer math questions.An instructor read out numbers- 74，470，70，809，98，402- and Stevenson added them in her head.For each question，she closed her eyes，and then the fingers of her right hand began to move.She answered most of the problems correctly.
   The key to her success was an ancient technology called the abacus （算盤）.Stevenson used a practice called "mental abacus"，imagining the abacus in her mind and then using her fingers to work through the problems.
   From watching Stevenson，I knew that gaining skill at the abacus was more than a matter of counting beads（珠 子 ），so I decided to sign up for an abacus course with my two daughters to see if we could also improve our math skills.I was one of the many who had some math doubts and I felt a touch of fear.My typical solution was avoidance，and if I had to calculate something like a percentage change，I would go online.
   Then after a few abacus classes and a good amount of practice，math seemed a little less frightening.I didn't become Euclid，the founder of geometry（幾何學(xué)）.But the practice brought my numerical fears down.This is a time-tested power of the abacus.Confidence grows easily in the device，and abacus students are less likely to be nervous about an upcoming math test，according to one study.Part of the reason，it seems，is that practice and outcomes appear to move in step.
   My kids gained much as well.My youngest daughter could work out those math problems that once baffled her，while my older child brought her abacus to school to show it to her classmates and teacher.These were just small successes for them，but that was how they finally developed confidence.

（1）What is the main purpose of the first paragraph？

C

C

A．To show the high intelligence of Stevenson.
B．To stress the importance of abacus learning.
C．To introduce the topic of the abacus.
D．To prove the difficulty of math.
（2）What do we know about the author from paragraph 3？

A

A

A．He was weak in math.
B．He was good at computer.
C．He regarded math as useful.
D．He had a close relationship with kids.
（3）What does the author realize from his learning experience？

D

D

A．Knowledge starts with practice.
B．It's never too late to learn.
C．Faith can move mountains.
D．Practice makes perfect.
（4）What does the underlined word "baffled" in the last paragraph mean？

B

B

A．Bored.
B．Defeated.
C．Interested.
D．Inspired.