The author implies that villagers liked LED bulbs very much, because they________.
A. were given by Irvine-Halliday
B. are rugged
C. are cheap
D. are easily-recharged
查看答案
What is mainly discussed in the text？
A. roast bean can cure disease.
B. roast bean is a good medicine.
C. more and more people want to drink coffee.
D. whether the roast bean is good or bad is also a question.
What is the typical scene found in the campus of Wesleyan University？
A. Pieces of chalk are scattered everywhere on the ground.
B. There are some meeting announcements on the billboard.
C. All kinds of messages are written on the paths.
D. Some people are shocked by the meeting announcements.
What worries her recently？
A. She cannot work in London.
B. She cannot live in London.
C. It is difficult for her to finish her studies.
D. It'll be difficult for her to find a job.
Which of the following statements does not agree with the facts in the passage？
A. The displays in digital clocks and calculators are just produced by early LEDs.
B. Irvine-Halliday believes that LED will certainly become the world's main source of artificial light
C. A decade ago, engineers developed red and blue LEDs, which were regarded as a mile-stone in this research.
D. It is the blue LED developed by a Japanese engineer that had a great impact on the research process.
微信支付 
支付宝支付