Analyze and comment on the following.He is as poor as a church mouse. Pick out the idiom in this sentence, then point out its structure, grammatical function and figure of speech.
(L)THE IDIOM IS “AS POOR AS A CHURCH MOUSE”.
(2)ITS STRUCTURE IS : AS+ADJ.十AS+N.
(3)ITS GRAMMATICAL FUNCTION： ADJECTIVE IDIOM AS PREDICATIVE IN THIS SENTENCE.
(4)SIMILE. 
