請將下面這段話翻譯成英文：

　　印刷術(shù)發(fā)明之前，想出版新書的學(xué)者必須一字一字地抄寫。北宋時(shí)期，經(jīng)過多年的實(shí)驗(yàn)，畢昇發(fā)明了活字印刷術(shù)(movable-type printing)。他把漢字刻在一小塊泥胚(pieces of clay)上，加熱漢字直到其變成硬的活字。印書時(shí),人們按順序?qū)⒒钭謹(jǐn)[在一起，印出印跡。印刷完后，他們把字分開，以后重復(fù)使用。這種方法既經(jīng)濟(jì)又省時(shí)。中國的活字印刷術(shù)首先向東傳至朝鮮和日本，之后向西傳至波斯(Persia)和埃及，最后傳遍全球�；钭钟∷⑿g(shù)的發(fā)明大大促進(jìn)了世界各國的文化交流。

　　參考翻譯

　　Before printing was invented，a scholar had to copy characters one by one if he wanted to publish a new book.During the Northern Song Dynasty, Bi Sheng invented the movable-type printing after many years of experimentation.He engraved the characters on small pieces of clay,and heated them until they became hard movable characters.When printing a book，people placed the moveable characters in order into a whole block and then ran off a print.After printing, they took the block apart and reused the characters later.This method was both economical and time-saving.China's movable-type printing first spread eastward into Korea and Japan,then westward into Persia and Egypt,and at last,around the world.The invention of movable-type printing greatly promoted the cultural exchanges among countries all over the world.