In ancient time，there was no iron casting，so the needles were made of ______.
A: stone
B: tree
C: iron
D: mental
A: stone
B: tree
C: iron
D: mental
举一反三
- The micro needle recorded in The Internal Medicine Canon of Huang Di, can only be made of ( ). A: cooper B: stone C: bian stone D: iron
- The cylinder block is a complicated casting made of gray iron(cast iron) or aluminum. 这句话的意思是机体是复杂的灰铸铁或铸镁件。
- The cylinder block is a complicated casting made of gray iron(cast iron) or aluminum. 这句话的意思是机体是复杂的灰铸铁或铸镁件。 A: 正确 B: 错误
- Iron replaced stone and timber in the building of bridges because iron was considered ______. A: more beautiful B: new and modern C: much stronger D: easier to transport
- 秦汉时期已经开始发展铁器成型技术，这句翻译为（ ） A: Iron casting technology has already been employed in Qin (220 to 205 BC) and Han dynasties (206 –220 BC). B: Iron casting technology has already been employed in Qin (221 to 207 BC) and Han dynasties (236 –210 BC). C: Iron casting technology has already been employed in Qin (221 to 207 BC) and Han dynasties (202 –220 BC). D: Iron casting technology has already been employed in Qin (221 to 207 BC) and Han dynasties (201 –227 BC).