Solidgeometryhasenabledastronomerstocalculatethepositionsoftheheavenlybodiesrelativetooneanother.
A、ontopofThe Native American interpreter Sacajawea was a valuable member of the Lewis and dark expedition in 1805.
Although the Carbon 14 method of dating old objects is not foolproof , it is the best method available at present
Anoversight遗漏(miss,overslaugh)inproofreadingoftenresultsinprintederrors.
Cream of tartar 酒石 , a weak acid, can be added to egg whites to help them foam泡沫 when they are beaten
Formerly , in the United States, many nurses worked as private duty nurses rather than in hospitals.
