what are you doing for vacation?你假期准备做什么?怎么会成将来时了呢?be doing

what are you doing for vacation?你假期准备做什么?怎么会成将来时了呢?be doing 不是进行时吗?那
什么时候才把他看成进行时表示将来呢?

现在进行时除表进行外,还可以表示将来.现在进行时表将来时常用“意图”“安排”或“打算”的含义.这种现在进行时比较生动,给人一种期待感.
看语境.
1.它常表最近或较近的将来,所用动词多是转移动词.如：
(1) I’m going. 我要走了.
(2) I'm coming.我要来了.
(3) When are you starting? 你什么时候动身?
2.表将来的现在进行时除用于转移动词外,亦可用于某些非转移动词.如：
(1) I’m meeting you after class. 课后我找你.
(2) What are you doing next Sunday? 下星期你打算干什么?
(3) She is buying a new bike soon. 她不久将买一辆新自行车.
3.但偶尔也表示较远的将来.如：
When I grow up, I’m joining the army. 我长大了要参军.
4.表将来的现在进行时有时含有“决心”的意思,多用在否定结构中.如：
(1) I’m not going. 我不走了.
(2) I’m not waiting any longer. 我不再等了.
5.有时也用在肯定结构中.如：
I’m backing out. 我要打退堂鼓了.
6.用这种现在进行时与对方讲话时可变成命令,不过语气比较温和.如：
(1) You are staying. 你留下吧.
(2) Don’t forget: you are taking part too. 不要忘记：你也要参加.
7.同一般现在时一样,现在进行时也可在时间、条件或原因状语从句中表示将来.如：
(1) when you are passing my way, please drop in. 你什么时候路过我们家,请进来坐.（用于时间状语从句）
(2) If they are not doing it, what am I to do? 如果他们不干,那我该怎么办?（用于条件状语从句）
(3) She is going to the dentist tomorrow because she is having a tooth filled.
8.表示将来的现在进行时也可用在间接引语中,表示说话人相信它将是事实.如：
He said he is going tomorrow. 他说他明天走.
9.表将来的现在进行时有时从属于将来时态.如：
(1) On election night we’ll be telling you what’s happening in various places in this country. 到了选举的夜晚,我们将把全国各地的情况告诉大家.
(2) when I have time, I’ll come down to the school to see how you’re both doing. 我有空时,会来学校看你们俩的学习情况.
典型例题
(1）He said he________me a present unless I_______ in doing the experiment.
A. had not given; had not succeeded B. would not give; succeed
C. will not give; succeed D. would not give; will succeed.
答案B. 在时间,条件或让步主语从句中一般不用将来时.本题有He said,故为过去式.主句用将来时,故选B. 此处用一般过去式代替了过去将来时.
(2) 表示现在已安排好的未来事项,行程等活动.
The museum opens at ten tomorrow. 博物馆明天10点开门.(实际上每天如此.)
I know you are arriving next Sunday.（我知道你下个星期天就要到了）进行时表将来,所以 arriving 后面+next Sunday.
你可以自己百度一下,资料很详细.