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英语翻译
1.Studies show that the virus is usually passed to an infant close to or during delivery,rather than moving across the placenta during pregnancy.Recently infected mothers can transmit the virus to their children via breast milk.The United States Congress approved guidelines recommending that health care workers who perform invasive procedures be tested for the AIDS virus but the testing and disclosure of results would be voluntary;no restrictions would be placed on those who tested positive.
2.The stratospheric vortex broke up later in the year.
1.Studies show that the virus is usually passed to an infant close to or during delivery,rather than moving across the placenta during pregnancy.Recently infected mothers can transmit the virus to their children via breast milk.The United States Congress approved guidelines recommending that health care workers who perform invasive procedures be tested for the AIDS virus but the testing and disclosure of results would be voluntary;no restrictions would be placed on those who tested positive.
2.The stratospheric vortex broke up later in the year.
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