Now we're lucky because prepositions are a closed group in English, a closed group.
现在我们很幸运，因为介词在英语中是一个封闭组，一个封闭组。
Closed group
原声例句
可汗学院公开课：英语语法
英语百科
Algebraically closed group
In mathematics, in the realm of group theory, a group 
is algebraically closed if any finite set of equations and inequations that "make sense" in already have a solution in . This idea will be made precise later in the article.
- George Mifflin的意思
- George M. Woodwell的意思
- George Nathaniel, 1st Marquis Curzon of Kedleston的意思
- Georgenberg的意思
- georgene的意思
- Georgensgmünd的意思
- Georgenthal的意思
- George of Cappadocia的意思
- George of Trebizond的意思
- George Orson Welles的意思
- george orson welless的意思
- George Orwell的意思
- George Orwell的意思
- George Otto Trevelyan的意思
- george otto trevelyans的意思
- George Paget Thomson的意思
- george paget thomsons的意思
- George Patton的意思
- George Percy Aldridge Grainger的意思
- george percy aldridge graingers的意思
- George Pitt的意思
- George Pitts的意思
- George position的意思
- George Pullman的意思
- George R.的意思