Je me lance sans garantie car je ne sais pas aux+been+verb-ing ou aux + verb-ing
1) Twelve years ago,she learnt that a mining company had obtained exploration rights from the government.
2) After several months she managed to halt the project and had been battling since then.
3) My mother had been(was) feeling lonely since we left home.
4) As soon as you have made up your mind, let me know.
Did you believe in ghosts ? I didn't until yesterday when I saw a person who died in 1972 (was?) walking about the streets of London ! I had just had lunch with some friends and I was leaving them when it happened. There she was, I was not believing ( couldn't believe) my eyes ! I knew she had been reporting dead in Vietnam in 1972.
Pas sûr mais j'espère t'aider un peu qd même. Gros pb avec I ....(not/believe) my eyes; instinctivement j'aurai mis couldn't mais je comprends pas trop : "sometimes a modal is necessary"...... pour "walk about" pareil" J'ai mis juste walking....... (I don't find the clue !!!)
Good luck; Hope I helped......................... a little, at least !!