【单选题】I don’t think ___ of his parents are home. They usually go out for a walk at the moment. [ ]
【简答题】The sellers are obliged to advise the Buyers of the expected date of shipment and the concrete quantity ready for shipment before the Buyers open letters of credit.
【单选题】下列哪项不是引起B细胞介导的免疫应答水平下降的原因
【单选题】感染HIV后,下列哪项不是导致机体免疫功能受损的主要机制( )
A.
被感染的CD4+淋巴细胞表面表达gp120,可与其他CD4+细胞相互融合,细胞被破坏
C.
HIV感染B细胞,能使其大量破坏,抗体生成减少
E.
感染HIV后诱发机体的免疫反应,使受感染细胞受到攻击而被破坏
【单选题】—I can't open the top of this apple juice. —______ it.
【单选题】科学技术是第一生产力,促使科学技术再生产的最主要途径是 ( )
【简答题】We usually think that ______ , but sometimes we ______ for ourselves.
【单选题】Business buyers are heavily influenced by factors in the current and expected economic environment, such as ________.
A.
level of primary demand
B.
organizational objectives