【判断题】高速钢是热硬性(热稳定性)、耐磨性很好的高合金工具钢。它的热硬性可达到600℃,切削时能长期保持刃口锋利,故又称为“锋钢”。
【单选题】Shopping habits in the United States have changed greatly in the last quarter of the 20th century.【C1】______in the 1900s most American towns and cities had a Main Street. Main Street was always in the...
【判断题】溯 洄 从 之 的从的意思是随从的意思。
【判断题】初凝时间是指自加水起至水泥浆开始失去塑性、流动性减小所需的时间。
【判断题】溯洄从之,道阻且长。溯游从之,宛在水中央。 这句诗歌的意思是: 溯洄(sù huí):逆流而上。洄:上水,逆流。从之:追寻他。沿着弯曲的河边道路到上游去找伊人。从:跟随、追赶,这里指追求、寻找。之:这里指伊人。道阻:道路上障碍多,很难走。阻,险阻,道路难走。 溯游从之:顺流而下寻找她。溯游,顺流而下。“游”通“流”,指直流的水道。
【单选题】Shopping habits in the United States have changed greatly in the last quarter of the 20th century.【C1】______in the 1900s most American towns and cities had a Main Street. Main Street was always in the...