“whose father worked for the railroad” is a subordinate clause as it is a relative clause beginning with the pronoun “whose”. It is particularly used in written English and it refers to possession of things or to make association or connections with other things or people.
I would say that the answer should be "Helen's challenges with the frustration of learning to communicate".as a blind-deaf person and the excellent analogy with being shrouded in fog and not having how to determine where she was headed but love giving her the light to find her way and eventually get a degree at university.
Answer:
1. He doesn't visit me
2.they are winning the match
3.I am busy watching TV Afzal said to me
4. he will come home.
5." why didn't you run fast ?" asked Sara
6. does he commit a mistake everyday?