harp on one (/the same) string; play the same old tune(/story/theme /refrain); sing the same old song(/tune) ? 你總是～，有誰欣賞呢？ You’re always harping on the same string. Who’d like to appreciate it?/現(xiàn)在他又開始～了。Now he’s started on his hobbyhorse.
舊調(diào)重彈
harp on the same string; play the same old tune; rehash old ideas
舊調(diào)重彈舊（老）jiù diào chónɡ tán
陳舊的曲調(diào)又彈奏了一遍。比喻把過時(shí)的理論和觀點(diǎn)重新拿出來，說得還是老一套。harp on the same old tunes, play back the same old story, play the same old tune, sing the old song again, beat over the old ground