come to/go to/arrive in (at)/get to/reach …→ be in/at…join the army → be in the army(军队)
e.g.I have borrowed the book.我已经借了那本书。
I have kept the book for two days.我已经借那本书两天了。
Jim has joined the band.吉姆已经加入那乐队了。
Jim has been a member of the band for a month.吉姆已经加入那个乐队一个月了。
His grandfather has died.他祖父已经死了。
His grandfather has been dead for 2 years.他祖父已经死了两年了。
My father has arrived in China.我父亲已经到达中国了。
My father has been in China for a week.我父亲已经在中国一个星期了。