题干

下列关于基因工程及转基因食品安全性的叙述,正确的是(  )

A:基因工程经常以抗生素基因为目的基因

B:通过转基因技术可获得抗虫粮食作物,从而增加粮食产量,减少农药使用

C:通常用一种限制性核内切酶处理的基因,用另一种限制性核酸内切酶处理运载体

D:若转入甘蔗中的外源于自然界,则生产出来的甘蔗不存在安全性问题

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B

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    English is one of the most difficult languages to master. Even if you might not yet sound like someone born and raised speaking the language, you should still congratulate yourself on how far you've come. Remember that practice makes perfect. So keep working at it and your skill level will certainly improve.

    Create an English environment for yourself.____The more you hear the language, the better you'll understand how and when to use common words and phrases and how the language is pronounced.

    Practise speaking English every chance you get, whether at school, at work or speaking to family and friends. When you speak in your native language, ask yourself, “How would I say that in English?”

    Watch yourself speak English in the mirror.____And practise changing anything you don't like. If you're uncomfortable making up things to say to yourself, just read your lessons aloud.

    Use confident body language while you speak English. Even if you're having trouble pronouncing words or remembering phrases, don't keep your head down. Speak in a natural, conversational tone(语气); keep your back and head straight, and your chin(下巴) up. If you're in a relaxed setting, put your hands behind your head and put your feet up.____

    Find a language friend who speaks fluent English and wants to learn your language.____Increase your confidence by knowing you have something valuable to teach, as well as something to learn.

____Instead of saying “I'm no good at this,” say “Every day I'm getting better.”

A. Take turns teaching each other

B. Train your body into feeling in control

C. Speak confidently about your English ability

D. Learning a language requires long hours of study and practice

E. Get comfortable with the way you look speaking the language

F. Read books, watch television shows, moves and plays in English

G. Improve your confidence by teaching those worse at English than you