That's because she was an activist for environmental protection. Green as an adjective often refers not to the color, but rather to describe someone who is environmentally friendly. In this case, her literature fought for preserving the nature and save the environment, so it is therefore green.
[A]
The theme of this story would being proud of who you are and this is shown when the narrators mother says “Your only shame is to have shame”.
1. impinge = strike
The word impinge can have various meanings, but in the case above, it means to strike. When 'the rain impinge[d] upon the earth,' it means that it started raining, the rain started striking the earth. To impinge means that something starts, and usually something negative.
2. garrulous = loquacious
The word garrulous refers to someone who talks excessively, likes to talk a bit too much, and usually about something trivial. Loquacious is a fancy word to denote the same thing, although it has a more positive connotation - it refers to someone who can speak nicely.
3. pious = religious
The word pious comes from the Latin word pius, which means dutiful. So when English took this word from Latin, it added a different suffix (-ous), and gave it the meaning of being 'dutiful to God.' So nowadays, pious refers to someone who is devoutly religious.
4. ruinous = dilapidated
The word ruinous refers to something which is in ruins, which is falling apart. The word which means the same thing is dilapidated - both of these words are usually used to describe buildings that are very old, and derelict, and are practically in ruins.
