I have a ____(三天）holiday.应该添什么?标准答案是three-day.可以是three days`么; 为什么three days不对?不是有have a three days off这个短语么.我完全混了

I have a ____(三天）holiday.应该添什么?标准答案是three-day.可以是three days`么; 为什么three days不对?不是有have a three days off这个短语么.我完全混了 判断：I have a pen.____ I have pen.____ I have a sore throat.（同义句） I ____ ____ ____.（一空一词） I have a toothache.用两种方式提问____ ____ ____ you?____ ____ ____ ____ you? have a sore throat同义句 I ____ ____ ____. Can I have a look at your ____（菜单） I have a ____（real）busy day. I have a pain in my head today (同义） I ____ ____ _____ today i have holes on the top and botton.and i have holes in the middle,yet i still hold water.i have hol I have just received a letter from my brother.（同义句）=I have just ____ ____ my brother. I have a family ____ three. ____ a busy day I have.填空 I have a sore throat.同义句.I ____ ____ ____ ____. I hope you all have a wonerful time.=I hope ____ ____ ____ have a wonderful time.（同义句） I hope you have a good trip.(同义句）I hope you have a good trip.（同义句）I ____ ____ a good trip i have a pain in my throat改同义句下面i have a ____ ____. I also have one sister .(改写成同义句）I have ____ ____,____. I have a friend called Tom.(同义句） I have a friend ______ ________ ____ ________ Tom.I have a friend called Tom.(同义句）I have a friend ______ ________ ____ ________ Tom.