1. i the truth. a) to learn b) to be learnt 2. she was glad her friend a) to see b) to have seen 3. a young boy was surprised to the ball a) to have invited b) to have been invited 4. the actor liked a) to be interviewed b) to have been interviewed 5. english is very pleasant a) to speak b) to be speaking

1. а), 2.а),3.b),4.b),5.b).

We WERE LOOKING(look) for the station and itWAS RAINING(rain). Anyway, weWERE LOOKING(look) at our map when weMET(meet) an old lady. SheDIDN'T(not know) the way to the station, but she GAVE (give) us her umbrella! 2 When I was a child, IVISITED(visit) my grandparents every weekend.They HAD (have) a dog called Bono. One day, I WAS WALKING (walk) the dog when I GOT (get) lost. I WAS (be) lucky because a woman from the village FOUND (find) me and CALLED (call) my grandma. 3 Yesterday I WAS WAITING (wait) in my car at a traffic light. An old manWAS CROSSING(cross) the road with two bags of shopping when heDROPPED(drop) one of his bags. IGOT OUT(get out) of my car andHELPED(help) him pick it all up. 4 Last week, IWAS STANDING(stand) in a ticket queue in the London Underground when a girl GAVE (give) me her train ticket. She DIDN'T WANT (not want) any money for it, she just wanted to give it to someone else .

Maluerindi is very sad because nobody else in the world can speak his Aboriginal language. 
Experts who study languages say that fifty one languages are dying now and they think about three thousand languages will disappear in the next 100 years
There are many reasons why languages die but the biggest one is that such big world languages like English, Spanish, Portuguese and French are becoming more and more popular and it's hard for small languages to survive. 
If people want to save their language, they need to record the language.  Then they need to train teachers, and write grammar books, dictionaries and books for schools.
We should care about languages that are in danger (just as we should care about rare plants and animals).If a civilization dies, it leaves behind buildings. But a spoken language leaves nothing behind- when it dies, there is only silence.