Three years ago, researchers announced the discovery
of human genes that were capable of turning ordinary cells into malignant ones.
The news met with some skepticism. Experts asked how a single gene could cause
such a dramatic change. Why does cancer take years or even decades to develop if
it is caused by such a simple and direct process In last week’s issue of the,
three research teams answered those questions by setting forth a new model for
understanding the role of oncogenes in cancer. Each group found that it does in fact take more than a single gene to produce cancer in normal cells. Teams at M. I. T and Cold Spring Harbor Laboratory on Long Island, N. Y. , reported that they could induce cancer in normal rat cells only by inserting at least two types of oncogene into the cells. "A single oncogene produced some changes, A. was caused by normal cells B. sometimes resulted from internal actions of the victim’s own body C. was a hereditary disease D. was a form of malignancy [单项选择]More than three years after moving from Australia to this remote point of England, we are still learning how things have done here.( )
A. More than B. remote C. still D. have done [多项选择]You have spent almost three years in your university, and lectuers of different kinds have been in your classes. Some may be famous in a certain field, while others give you the individual attention that you need. Some may encourage you to express your ideas freely, while others are better at leading you to think critically. Among all the lectuers you have been in contact with or heard of, what are the qualities that you value most Write an essay of about 400 words on the following topic:
The University Leetuers’ Qualities That I Value In the first part of your essay you should state clearly your main argument, and in the second part you should support your argument with appropriate details. In the last part you should bring what you have written to a natural conclusion or make a summary. Marks will be awarded for content, organization, grammar and appropriateness. Failure to follow the above instructions may result in a lo [单项选择]Exactly three years before the year in which Anna was born, the year was 1980 x. In terms of x, on Anna’s twentieth birthday, the year will be ?()
A. 1977+x B. 1997+x C. 2003-x D. 2003+x E. 2006+x [单项选择]
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