问题
单项选择题
焊剂在焊接时是用来()焊料和防止焊面氧化的。
A.润湿
B.干燥
C.腐蚀
D.氧化
答案
参考答案:A
焊剂在焊接时是用来()焊料和防止焊面氧化的。
A.润湿
B.干燥
C.腐蚀
D.氧化
参考答案:A
请先阅读下面短文,掌握其大意,然后从方框中所给的词中选出最恰当的10个,用其适当形式填空,并将答案填写到答题卷的相应位置。每个词限用一次。(每小题1分)
in China. The earliest book 小题2: in 868 and was found in a Dunhuang cave. Wood-block printing took a long time because a new block was needed for every 小题3: in a book. By the 11th century printed books could be 小题4:all over China. They included books of Confucius' thoughts, dictionaries, and books on maths. In 1340, books could be printed using two 小题5: - black and red. Although the Chinese learnt about printing so小题6: , printing was not introduced in other parts of the world for hundreds of years. It is thought that when the great Italian traveler Marco Polo visited China in the 13th century, he saw printed books. It is possible that Marco Polo brought that 小题7:to Europe. But printed books did not come to Europe 小题8:1450 when a German called Johann Gutenberg 小题9:a printing machine. Twenty-four years later, in 1474, an Englishman called William Caxton printed the 小题10: printed book in English. His second book was about the game of chess. Caxton printed about a hundred books, and some can still be found today in museums. |