Tempos verbais em inglês - teste

Boa noite pessoal,

Sou uma das milhares de alunas e alunos que tem dificuldades com os (malditos) tempos verbais. Estava eu fazendo um teste na internet, para fins de estudo. Como nesse teste final nao me retornava as respostas certas eu fiquei sem saber o que acertei ou o que errei.

O que está em [x] foi minha resposta e o que está entre () é o que eu classifquei, nao sei se está certo ou nao. Desculpem abusar da boa vontade, mas isso vai me ajudar muito a avaliar a quao andas meu entendimento. Obrigada antecipadamente

1) Prisoners in North Mexico _ over six months digging a tunnel in an attempt to escape from prison.
[x]spent (simple past)
Have spent (present perfect)

2) They _ in that school for a long time when they decided to move.
[x]had studied (past perfect)
Have studied (present perfect)
Studied (simples past)
Had been study (past perfect continuous)

3) He _ his key and now he can't get into his flat.
Has been losing (present perfect continuous)
[x]had lost (past perfect)
Has lost (present perfect)
Had been losing (past perfect continuous)

4) It is believed that _ on a farm has a lot of positive points.
Grow up (simple present)
[x]grows up (simple present)
Growing up (present continuous)
[x]has grown up (present perfect)

5) _ in the garden all morning and I still _ .
I've worked / haven't finish
[x]I've been working / haven't finished
I worked / didn't finish
I will work / will finish

6) By the time he finishes one of his tasks, his sister _ .
[x]will be finished three of hers.
Will have finished three of hers.
Will have finish three of hers.
Will have been finished three of hers.

7) If I _ a big prize, I _ travel around the world.
Won / will
Will win / would
Won / -
Won / would