Personification, it is giving stars the humanly characteristic of dancing.
Answer:
key words : Perfect, shiny
author's tone : admirably
Yeats states that he was not closely acquainted with the people in the Easter Rising. He acknowledges that he only exchanged pleasantries with them before the uprising. He also indicates that he has personal reasons for disliking one person. So he is writing about the cause for which they stood, which, by inference, is important.
The comparison of the rebels to "stone" suggests that Yeats may have viewed the rebels' attitude as inflexible or not adapted to the changing times. Yeats also acknowledges the possibility that their deaths may have been "needless" because the British might keep their promises.
However, his reference to the "sacrifice" (of all who had supported Irish independence) and the rebels' "excess of love" suggest that he views their cause in a positive light. Moreover, Yeats's repeated description of the kind of change that the uprising has brought about as "a terrible beauty" suggests that his sympathies lie with the rebels.
To summarize, Yeats places a certain distance between the rebels and himself, but he supports the rebels' cause.
