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方程两边对y求偏导数有
I marvel that he _____, it having been said he had taken his final departure for Portugal.
The doctor suggested that he _____ an operation at once.
The crowd cheered _____ as she took the smoke-blackened bundle out of my arms—I had saved her baby!
Over five times more studies on life satisfaction have been published since 1979 than at any time_____
No particular stage of life is less happy than another, not the tumultuous teenage years or the mid-life period, not _____ the waning decades of old age.
The adoption of the new policy would relieve the factories_____a tremendous burden.
In the nineteenth century，Samuel Gridley Howe founded the Perkins School for the Blind，( )for children in Boston，Massachusetts.
My grandparents always enjoy the( )of their relatives.
The UN put the( )forward so as to better cope with the tense situation in the Middle East.
This country is( )deflationary pressure and the country′s policy-makers should create a better policy mix to cope with the new economic environment.
