15.
Bicycles are a great way to get around.They're fun to ride,especially down hills.And,as you speed along the road,you might also think of ways in which you could improve your bike-make it safer,more efficient,or more comfortable.In fact,the two-wheeled machines make for some cool science projects.
This year's Intel International Science and Engineering Fair (ISEF),held last May in Cleveland,featured (had) three bicycle projects from three countries.Like many of the other experiments presented at ISEF,the bike projects showed that some of the most interesting scientific research often begins by taking a closer look at things you care about.
Renato Angulo Chu had even greater ambitions.The 12th-grader from Lima,Peru,wanted to address some of his country's economic troubles,such as lack of electricity.
Renato,16,spent 3years designing his special Multi-bike,which looks like a fixed exercise bike but with lights ahead.It has wires fixed along the frame and a blender (食物攪拌器) fastened to the back.Turning the pedals operates the blender.The same principle can be used to sharpen knives or sweep city streets.
The Multi-bike can work either as a fixed bike or as a bicycle able to travel city streets and country roads."You pedal the bike,and you can mix any drink you want,"Renato said.More importantly,he added,the same concept could be used to bring light to houses in remote regions of the rainforest.
68.What can we learn from the first paragraph?C
A.Bicycles are the best way to go about
B.Bikes should be made more comfortable to ride.
C.You can improve your bicycle for science research.
D.Many inventions are connected with the bicycle.
69.Which of the following is true according to the passage?B
A.ISEF is an exhibition displaying bicycle experiments.
B.Looking closely at things can lead to scientific research.
C.Renato's work has solved the country's great problem.
D.Renato's bicycle will soon be put into use in remote areas.
70.The underlined word"address"in the third paragraph probably has the same meaning asC.
A.have addresses written B.give up C.work at D.speak about
71.It can be inferred that Renato's special bicycle is mainly designed forA.
A.distant areas in the rainforest without electricity.
B.the use of his own family to make life easier.
C.winning money to support remote rainforests
D.getting enough exercise by pedaling it.