问题 多项选择题

下列关于生长因子的说法中,正确的一项是()

A、是微生物生长不可缺少的微量有机物

B、是微生物生长不可缺少的微量矿质元素

C、主要包括维生素、氨基酸和碱基等

D、一般是酶和核酸的组成成分

答案

参考答案:A, C, D

多项选择题
完形填空

选编(十六)

Dorothy Brown was very happy as she sat in the theatre listening to the music. Today her little daughter Lauren was giving her ___1___ concert. She had been waiting for this ___2___ for years and years. “Now it is here at last,” she thought. “How beautiful her ___3___ is.”

The song made her ___4___ to the days when she was Lauren’s ___5___. As a young ___6___, Dorothy wanted to be a concert singer. She studied ___7___ in France, Italy and in the United States. “You can become a fine ___8___ in the future,” her teachers told her. “But you must be ___9___ to study hard and work for many years. There will be ___10___ time for anything but music in your life.”

Dorothy was ___11___ at that time and she was ___12___ that music was all she wanted or needed to ___13___ her life. For almost a year Dorothy ___14___ of nothing else. Then she ___15___ David, a young engineer travelling Europe. They soon fell in ___16___. David asked her to be his ___17___. Dorothy also wanted to marry David. But she loved ___18___, too. She didn’t know what to do. David was against her being a singer. He said, “If you want to be a singer, you must forget about getting married. You can’t ___19___ do both.” Thus her days were gone and would never return.

Now Lauren became a singer instead of her, which was her ___20___.

1. A. sorry              B. successful           C. first         D. wonderful

2. A. dance              B. moment             C. show          D. party

3. A. voice              B. face                  C. dress          D. life

4. A. think of                  B. bring back           C. go back         D. come back

5. A. age                    B. friend               C. mother                D. teacher

6. A. musician                 B. pop star               C. lady                  D. girl

7. A. French            B. music                C. piano            D. dance

8. A. actress              B. student               C. singer         D. dancer

9. A. prepared           B. learning             C. driven         D. waiting

10. A. some              B. any                    C. no            D. enough

11. A. eight              B. eighteen              C. eighty         D. eighty-eight

12. A. lucky             B. sure                  C. afraid        D. fond

13. A. fill                     B. live                   C. lead          D. take

14. A. heard               B. knew                C. talked          D. thought

15. A. saw off           B. learned from       C. heard of      D. met with

16. A. love              B. feeling               C. music        D. touch

17. A. assistant         B. teacher               C. wife          D. student

18. A. him              B. engineering         C. herself       D. music

19. A. certainly          B. possibly              C. only          D. mainly

20. A. thought         B. hope                C. purpose      D. will