when he was in his thirties,he joined the Party.爲什麼填join啊 而不

題目：

when he was in his thirties,he joined the Party.爲什麼填join啊 而不是 take part in

解答：

他三十多歲的時候入黨
入黨 jion+組織是比較正式的
take part in或participate in多用於參加活動,非正式 再答： My pleasure~~