1. Look! A new hospital (build) near the airport.
Look! A new hospital has been built near the airport.или A new hospital is being built near the airport. - возможны оба варианта. В первом предложении говорится, что больница построена, не указано когда, значит, ставим Present Perfect Passive. Во втором предложении говорится, что больница строится, т.е. строительство еще не закончено - Present Progressive Passive.
2. Where these photographs (take)? In London? You (take) them?
Where have these photographs been taken? (Present Perfect Passive - не сказано когда произошло действие) In London? Have you taken them? (Present Perfect Active)
3. Two people (arrest) last night.
Two people were arrested last night. (Past Progressive Passive - образуется was/were + глапгол в 3 форме)
4. The computer broke down yesterday, but now it's OK. It (work) again. It (repair).
The computer broke down yesterday, but now it's OK. It is working/works again. ( Present Progressive/Simple Active). It has been repaired. (Present Perfect Passive - не сказано когда произошло действие, это страдательный залог, так как it=computer - подлежащее не само совершало действие, т.е. сам компьютер ничего не чинил)
5. The man next door (disappear) six months ago. Nobody (see) him since then.
The man next door disappeared six months ago (Past Simple Active - слово-подсказка ago. Nobody has seen him since then. (Present Perfect Active - слово-подсказка since)
6. The room looked nice. It (clean).
The room looked nice. It had been cleaned. (Past Perfect Passive - это страдательный залог, т.к. it=room - подлежащее не само совершало действие, сама комната ничего не убирала/мыла)
7. There's somebody walking behind us. I think we (follow).
There's somebody walking behind us. I think we are being followed. (Present Progressive Passive - в предложении говорится, что не мы за кем-то следуем, а нас кто-то преследует)
8. A mystery is something that can't (explain).
A mystery is something that can't be explained. (Passive Voice with a modal verb - страдательный залог с модальным глаголом. "Загадка - это то, что нельзя разгадать/что не может быть разгадано")
9. I'm sure that by the time we come to the theatre, all the tickets already (sell).
I'm sure that by the time we come to the theatre, all the tickets will have already been sold. (Future Perfect Passive - "... к тому моменту как мы придем в театр, билеты будут раскуплены)
Some months ago I set my first sail across the Pacific Ocean. I left Shanghai in order to reach New York. Unfortunately my steamship `Best voyage` submerged under mystic circumstances. I appeared alone on a small island in the Pacific Ocean. I was shocked... But indeed, I`ve found it nice here: blue water, high palmtrees, yellow sand and bananas. It`s like the paradise on the Earth. Nevertheless I miss my parents.
So, if you read my note, please, call my parents, Fang and Bao Tang. They live in Shanghai on Zhenning Road, 485. They would be glad to know that I`m happy enough and resting a big deal on the island. But don`t rush to save me. There are still many bananas and kakoses, I won`t be hungry for several years.
Good luck in searching me. I`ll be patient. Remember me to my parents.
Chan Tang, lost somewhere in the Pacific Ocean!