【判断题】硬质合金是用粉末冶金法制造的合金材料,由硬度和熔点很高的碳化物和金属粘结剂组成。( )
【单选题】若 x 3y = y 2x-5y = 6x-15y x ,则 4 x 2 -5xy+6 y 2 x 2 -2xy+3 y 2 的值是( )
【单选题】下列运用等式的性质,变形正确的是 [ ]
【单选题】He can speak English a native speaker.
【单选题】Can Mr. Smith, _____ native language is English, speak Chinese fluently? [ ]
【单选题】The constitutional guarantee of free speech may have been aimed at protecting native speakers of English from censorship, but it is not a great ______ to interpret it as protecting the right to expres...