The students went into the classroom 对的
后面是对的,进去的同时说着笑着,说笑正在进行着那我在作文里这样写也没问题吧？He stood in the doorway， looking at the window.应该没问题The students went into the classroom, talking and laughing这是个经典句型He stood in the doorway， looking at the window.，应该也可以