What are the four-word idioms that describe "very old"?

Old? [lM:o tàI lóng zhūng]: Longling: It doesn't look very active. Describe old age, weak body and inconvenient movement.

Out: Song Luyou's poem "Listening to the Rain": "Old age is uneven; This is more worthy of secular things. "Tang Li Rui's Gift to Xue Dai": "Friends are ashamed of the times; Dragon bell is like an old man. "

Old-fashioned [l m:o q chéng qiū]: old-fashioned: the style of the elderly; Horizontal: full. Describe the appearance of sophistication and conceit. Now it is described as arrogant and conservative. It also describes a lack of vitality.

Out: Northern Mountain Movement by Confucius in the Southern and Northern Dynasties: "Customs are all over the sky; First frost is in autumn. "

Depression? [mq? ché n ché n]: Twilight: the haze at dusk; Weight: low. Describe listlessness and lack of vitality.

Out: Song visited Mao and his son Keshan: "The building is uneven and faint."

Rely on the old and sell the old? [yǐ l ǐ o mà i l ǐ o]: sell: show off. Take advantage of your age and put on your old papers.

Out: Yuan Anonymous "v. Qingfengfu Demolition Case": "I will let you say a few words; Then lean on the old and sell the old; I can't speak. "

The boy whose teeth have fallen out? 【 chǐHu tóu tóng 】: Tooth loss and baldness. Refers to old age.

Source: Song Chen Shidao's poem "Su Chai Cheng": "I buried the dust leaves and started to smoke. My teeth are not a few years."