何歳ですか？ いくつですか？ 年齢は？ お年は？ I think all are question sentences of "How old are you?" which are they differ?what are most poilte form??
Consider this phrase: 今は(event)二十分前です。 Deconstruction of the above phrase yields: Now is twenty minutes before (event). (Q1) Can I reconstruct the statement using 後 in this manner?: ...