求It is three years since he worked in his office.解释下since

He l_____young!It's an o_____photo.my father is forty-three years o__now. it is three years since we____(most recently) met each other at david's part 求It is three years since he worked in his office.解释下since 句子中的S是has还是is(或was)?It's three years since he leave here.为什么? I have been here for three years.=It is three years ______I____here It's three years since he was married .的翻译 It is three years since she was in the 英语翻译还有这句 It'It's three years since I was a solder.It'It's three years since I joined the army How far is the Happy Valley from here?A It s three hundred metres in widthB It s one hundred kilogramsC It s twelve years oldD It s two metres long It's three years since we saw each other last time = We _____ _____ each other for three years lucy has been away from hei home for three years等于 it's three years ______lucy ___ __________ It is three years since he died.(同义句） He has ____ _____ for three years. he has been a soldier for three years.改为同义句：It is three years --------- ---------- ---------the army. my age today is three times what it will be three years from now minus three times what my age was three years ago.how old am we think it possible to learn English well in three years.为什么不是it is possible? it is an o___photo.My father is forty-three years old now It's three thirty.对three thirty提问,—— ——is it? 一道英语单选题 帮忙选答案解释原因You alaways talk about your pet dog,What's it like?A.It likes meat.B.Three years old.C.It is small and white.D.It likes playing with me.