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更多“when referring to ireland，peop…”相关的问题
A、down
B、off
C、by
D、with
从供选择的答案中选出应填入下面一段英文中______内的正确答案。
A light-emitting diode (LED) is a semiconductor(1)that emits visible light when an electric current passes throughit.The light is not particularly(2), but in most LEDs it is monochromatic, occurring at a single(3). The output from an LED can range from red (at a wavelength of approximately 700 nanometers) to blue-violet (about 400 nanometers). Some LEDs(4)infrared (IR) energy (830 nanometers or longer); such a device is known as an infrared-emitting diode (IRED).
An LED or IRED(5)of two elements of processed material called P-type semiconductors and N-type semiconductors. These two elements are(6)in direct contact, forming a region called the P-N junction. In this respect, the LED or IRED(7)most other diode types, but there are important(8). The LED or IRED has a transparent package, allowing(9)or IR energy to pass through. Also, the LED or IRED has a large PN-junction area whose(10)is tailored to the application.
供选择的答案：
1．wavelength 2．shape 3．emit 4．device 5．resembles
6．bright 7．visible 8．consists 9．differences 10．placed
The term "after" referring to date of shipment is inclusive of the date mentioned.( )
B、Refer to
C、Referring
D、With refer to
The words( ) applying to any date or period in the credit referring to shipment will be understood to include the date mentioned.
A. until B. from C. after D. to
By referring to Sam's broken bicycle, the author intends to ______.
A．illustrate the ways to repair his bicycle
B．discuss the problems of his bicycle
C．tell us how to solve a problem
D．show us how simple it is to repair a bicycle
A. to B. till C. after D. from
Listening takes place in four stages__________.
A. attention, interpretation, evaluation and action.
B. perception, judging, evaluation and action
C. perception, interpretation, referring and action
D. perception, interpretation, evaluation and action
