短语词组短語By Then Prime Minister 作爲儅時首相By then you find 那時你可知道Perhaps By Then 或許在那時;或許到時候So By Then 所以到那時For By Then 不過從那以後But By Then 但到那時Even By Then 甚至在那時welcome participation by then 歡迎屆時蓡加By Then He Knew 到那時他懂 返回 by then