It causes an estimated five thousand deaths each day,为什么要加数词an?

It causes an estimated five thousand deaths each day,为什么要加数词an? 英语翻译California regulators ,the first to brand secondhand smoke an air pollutant ,are convinced it causes breast cancer in younger women. Rewarding this behavior causes it to proliferate怎么翻啊? 英语翻译1.Lack of sleep causes declines in a desire limiting protein hormone.2.Lack of sleep causes declines in an appetite suppressing protein hormone.3.The program has had several gay contestants on it,but none has made it so far while being ma 帮忙写一下有关地震的英语对话要求：（两个人的对话,大学的）Talk with your partner about the causes of an earthquake,the damages it brings and the ways to cope with it. 英语翻译Dear Chinese Customers or to whom it may concernPlease do not use chinese letters in our shop,it causes enormous transmission problemsConfirmation of an order only means that we confirm receipt of your order,not availability of the specie This is an importnant piece of r_____ into the causes on cancer and DHT is an important part of male fetus development that causes baldness. 3837 什么意思 AN INQUIRY INTO THE NATURE AND CAUSES OF WEALTH OF NATIONS怎么样 AN INQUIRY INTO THE NATURE AND CAUSES OF THE WEALTH OF NATIONS怎么样 AN INQUIRY INTO THE NATURE AND CAUSES OF THE WEALTH OF NATIONS VOLUME 1怎么样 AN INQURY INTO THE NATURE AND CAUSES OF THE WEALTH OF NATIONS怎么样 英语翻译when the enemy is over the mine the touch of an electric button causes it to spring out of the ground until it is checked by a chain at the height of a yard above the surface,when it explodes,mowing down every man in the vicinity.请完 causes是什么意思 -What a nice day .-Yes,I like ___ when the weather is fine .A.one B.that C.it D.this___ unexpected heavy rain usually causes ____ great change .A.The;the B.An;不填 C.An;the D.The;a 请说明原因 英语翻译The AIDS virus has became a symbol for the global spread of disease in a shrinking world.It is an epidemic,globe in scope ,with the number of people infected with HIV-the virus that causes AIDS-climbing to more than an estimated cost 70 m It is evident that the causes of this phenomenon is diverse.帮我检查一下,有误语法错误 It is not I wants to be willful,the realistic reason causes me to turn this.