This is a serios problem for me. When we use active or passive ?

Dear Mrs Patel,
We are delighted to inform you that you 1 (select)for a free holiday. According to our information, you 2(answer) a telephone survey last month, as a result of which your name 3( enter)in the holiday draw.Now our computer 4(choose) your name, so you and your family5.(invite) to spend a week in a European destination of your choice.This offer 6(make) on the condition that you attend a special promotions day with other lucky families in your region who 7(offer) a similar deal.You 8.(ask) to attend on any Saturday next month at the Royal Hotel,Manchester.If you 9(interest) in attending and taking up this offer, please 10(detach) the slip below and return it to us as soon as possible.

In my opinion
1)have been selected - this is the example ( I can't understand why this is the correct form. Why not you are selected.
2) answered (because of last month )
3) has been entered ( present perfect beacuse it's a result of something and passive because we don't understand who entered this name.
4)First I thought that it must be past simple but I saw NOW and then decided that it should be has chosen
5)are invited (I decided to be in this way because of the translation which seems to be the very best way !
6)makes ( I think that it is active form because we know that the OFFER makes it not somebody else. and present simple because the other verb in the sentence Attend is also in present simple.After deep thinking I think that it can also be is made. It depends on the translation.
7)offers - active because we know who offers and the present simple because of that it is regular activity
8)are asked ( passive form because somebody who is not mentioned asked us and about present progressive because it is something already decided Saturday next month I think that are going to be asked is also possible but I am not sure. I'd be glad to understand if it is possible.
9)are interested - because interested is almost always used in passive and the transation clearly show us that it must be passive
10)detach - I am not sure about this but I think it is active it can not be passive and is present simple because ofreturn
If somebody spots some mistakes let's show them to me please!
1)have been selected - present perfect because the selection has recently finished.

2) answered YES

3) was entered PAST COMPLETED

4) has chosen YES

5) are invited YES


7) have been offered BY THE PROMOTER

8)are asked YES

9)are interested YES

10)detach YES

Don't worry so much about the meanings of the individual verbs-- concentrate on whether the subject is the doer (active) or the receiver (passive) of the verb's action.
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thanksEmotion: smile Is it possible to use ''are going to be asked '' in 8 gap.
I thought about 'will be asked', Max, but rejected it: they are asking now, in the letter to Ms. Patel.