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【单选题】
Which of the following is true according to the passage?A.
When a patent becomes out of effect, it can be re-patented or extended if necessary.
B.
It is necessary for an inventor to apply for a patent before he makes his invention public.
C.
A patent holder must publicize the details of his invention when its legal period is over.
D.
One can get all the details of a patented invention from a library attached to the patent office.
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【简答题】药物过敏性口炎属于( )型变态反应,接触性口炎属于( )型变态反应。
【简答题】接触性口炎属于__________型超敏反应。
【简答题】A borrower can get a mortgage from a bank, credit union, or other lender. Most lenders _____ the borrower to have a certain amount of money to use as a down payment. For example, if an ______ wants to...
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