题目

下列说法正确的是( ) A.混合物一定是由不种分子构成的 B.由同种分子构成的物质一定是纯净物 C.含有氧元素的化合物一定是氧化物 D.离子是带电荷的微粒，带电荷的微粒一定是离子  答案：B解析:略  完形填空。 Kangkang: Hello, are you Michael?Michael:      Yes, I __1__ .Kangkang: I'm Kangkang. How __2__  you do?Michael:    __3__ do you do?Kangkang: Where (哪里) are you from (来自)?Michael:     __4__ from Canada (加拿大). Are you from Beijing?Kangkang: __5__ , I am. Welcome to __6__ , Michael.Michael:   __7__ . Kangkang, this __8__ my mom.Kangkang: Nice to meet you!Mom:    Nice to meet you,__9__ .Kangkang: See you later.Mom and Michael: __10__ you. Good-bye!Kangkang: Goodbye. (     ) 1. A. am(     ) 2. A. are(     ) 3. A. What(     ) 4. A. I(     ) 5. A. OK  (     ) 6. A.    (     ) 7. A. Good(     ) 8. A. is(     ) 9. A. too(     ) 10. A. Meet B. isB. isB. HowB. I'mB. YesB. B. NiceB. amB. toB. See C. are      C. do       C. And      C. This is  C. Fine     C.          C. Thanks   C. are      C. please   C. Thank