in the 18th century和in 18th century有区别吗?

in the 18th century和in 18th century有区别吗? Realistic novel in the 18th century Europe in the 18th century是什么意思 初中英语in the 18th and 19th century in the 16th century什么意思 in the 20th century是什么意思 1.原文中有句话：Sandwich lived in the 18th century 英语单项选择 急1.In the 18th century writers__hours in coffee hours 7In the 18th century writers___hours in coffee houses,discus 9.The story is the 18th century in Canada.（ ） 想要知道翻译 since the founding of Taipei in the 18th century, early in the 18th century是译成早在18世纪 还是18世纪初期