in the end~In the end,he killed himself.in the end =finally,at last.最后他還是自殺了
at the end of~At the end of this street a body lay there.街尾躺著一具尸體
by the end of by the end of this year,they will have finished work on the new stadium(在今年年底工人們很把路鋪好）注：have+過(guò)去分詞表將來(lái)完成時(shí)
by表：在某時(shí)之前,并不晚于某時(shí)的任何時(shí)間.只能與時(shí)間點(diǎn)的名詞或詞組連用.在肯定與否定句中有區(qū)別
i will have left by monday到星期一我將離開(kāi)（星期一之前的任何時(shí)間）