How long has he been in office ?(他任職多久了？)

How long have you been married?(你結婚多長時間了？)

How long have they been at war ?(他們交戰有多長時間了？)

How long can you balance on one leg?(你單腿能站多久？)

What do I think about it? How long have you got?(我是怎么想的？說來話長，你有工夫聽嗎？)

How long have you been unemployed?(你失業多久了？)

How long have you had digital?(你們有數字電視多長時間了？)

How long has he held office?(他任職有多久了？)

How long did you spend on your homework?(你做家庭作業用了多長時間？)

How long does the play last?(那出戲要演多長時間？)