Edward Jenner　discovered（）at the end of the 18th century.

猜你喜欢

• Stanley Milgram of Yale University discovered that people are connected by “six degrees of separation”.；This means：
• In the spring of 1961， Yuan planted the seeds of the mutant in a pioneering field， proving that the plant， discovered in 1960， w
• The Terracotta Army was discovered on 29 March（）by a group of farmers digging a water well， about 1.5 kilometres east of the Emp
• Scientists have discovered how to predict an earthquake .
• It was discovered that the bodies of the diabetics had something in common: the group of cells in the（）was always damaged.