在级配砾石中掺石灰修筑基层，主要是为了提高基层()。

对历史人的描述应更多的体现为A．对历史人生活时代的描述 B．对历史人生存环境的描述 C．对历史人心理活动的描述...

单项选择题对历史人的描述应更多的体现为

驾驶员丧失能力，如需吸氧，将氧气选择在（ ）位，把应急供氧开关旋扭并按（ ）旋转A．100% 顺时针...

单项选择题驾驶员丧失能力，如需吸氧，将氧气选择在（ ）位，把应急供氧开关旋扭并按（ ）旋转

We wanted to entertain our guest but knew it would be _...

单项选择题We wanted to entertain our guest but knew it would be _____ to take him to an art gallery or the theatre as he was blind ( ).