单词学习YZ

Y 

year - n. a period of time equal to twelve months

yellow - ad. having the color like that of gold or the sun 

yes - ad. used to express agreement or to permit 

yesterday - n. the day before today 

yet - ad. at some time before now ("Have they arrived yet?"); now; at this time ("I 
cannot tell you about it yet."); conj. however ("The sun was shining, yet it was 
cold.") 

you - pro. the person or persons being spoken to 

young - ad. in the early years of life; not old 
 
 
Z 

zero - n. the number meaning none or nothing

zoo - n. a place where animals are kept for the public to look at and study  
  
  
 
COMMON PREFIXES 

dis - not (dishonest, disobey) 

pro - for, supporting (pro-labor, pro-government) 

re - to do again (reorganize, reunite) 

self - used to show that the person or group acting is the one affected by the action, 
or to show that the action is done only by its own effort or power (self-declared, 
self-appointed) 

un - not (unusual, unhappy) 
 
 
COMMON EXPRESSIONS 

carry out - to do; to put into effect ("Please carry out the plan.") 

pass a bill - approve ("Congress is expected to pass a bill to cut taxes.") 

take steps - to start to do something ("The government will take steps to halt 
inflation.") 
  
 
 
WORDS USED IN  VOA SPECIAL ENGLISH 
SCIENCE PROGRAMS 

atom - a very small part of all things; the smallest part of an element that can join 
with parts of other elements 

bacteria - living things that are one cell and can be seen only through a microscope; 
some cause disease 

cell - a small mass of living material that is part of all plants and animals 

chromosome - a line of genes; most human cells contain 46 chromosomes 

compound - a substance containing two or more elements 

dense - close together; thick 

electron - a small part of an atom that has an electrical force 

element - one of more than 100 substances known to science that cannot be 
separated into other substances 

enzyme - a special kind of protein; it produces changes in other substances without 
being changed itself 

fetus - unborn young 

fission - a splitting; in atomic fission, the nucleus of an atom is split to produce 
nuclear energy 

fusion - a joining together; in atomic fusion, atomic particles are joined together to 
produce nuclear energy 

genes - parts of cells that control the growth and development of living things; 
genes from the mother and father are passed to the child; genes contain nucleic 
acid 

genetic engineering - the science of changing the genes of a living organism 

gravity - the force that pulls things toward the center of the earth 

image - a reproduction of the appearance of a person or thing 

laser - an instrument that makes a thin, powerful light 

magnet - a piece of iron or other material that has a pulling force; this pulling force 
is called magnetism 

molecule - the smallest amount of a chemical substance that can exist 

nerve - a thin piece of tissue that sends information through the body to and from 
the brain 

nucleus - the center part of an atom or cell 

nucleic acid - a molecule that holds the genetic information necessary for life; there 
are two kinds of nucleic acid: DNA (deoxyribonucleic acid) and RNA (ribonucleic 
acid)

nutrient - a food or substance that makes plants, humans or animals grow 

organ - a part of the body that has a special purpose, such as the heart or brain 

organism - a living thing, often so small it can be seen only through a microscope 

particle - a very small piece of matter 

proteins - substances responsible for the growth of tissue and for fixing damaged 
tissue 

robot - a machine that moves and performs tasks 

tissue - living material; a group of cells that are similar in appearance and do the 
same thing 

virus - a kind of organism that causes disease 

x-rays - a kind of radiation that can pass through most solid materials, often used in 
medicine 
  
   
 
ORGANS OF THE BODY 

heart - pumps blood through the body 

intestines - tubes through which food passes after it is broken down in the stomach; 
part of the intestines also remove solid wastes from the body 

kidney - cleans liquid wastes from the body 

liver - makes some proteins and enzymes; removes poisons from the blood 

lung - takes in and expels air from the body 

prostate - a part of the male reproductive system 

stomach - breaks down food for the body to use 

uterus - a part of the female reproductive system where a fetus develops