连词成句since,the,is,he,ten,party,joined,years,in

it is ten years since he joined the party.少一个单词it。他参军10年了
句型：it is +一段时间+since+过去时某人做某事多久了

He joined in the party since ten years .

He joined in the Party since ten years .
应该是Party，而不是 party

He joined in the party since ten years .

He joined in the party since ten years