I have got some issues with comma usage. There are plenty of punctuation rules when it comes to participles. For exmaple:
I need to use commas:
- Hoping for a treat, the dog fetched the ball;
- The dog, hoping for a treat, fetched the ball;
- The dog fetched the ball, hoping for a treat.
I needn`t use commas:
- Sarah often saw the dog fetching the ball;
- The dog fetching the ball was mine.
Those exmaples are quite straightforward to me. However, yesterday, I wrote a graph description, using as much participle phrases as possible, and I was a little bit confused. Here are a few exmaples with "my" punctuation:
- There were an undeveloped route ( ) going through the village from the southwest to the north ( ) and a rail line ( ) passing from the southeast of the town to the northeast.
- The old road was extended (,) branching off to the east and connecting the village and Fonton.
- In the northern previously empty part, between Meadowside and Fonton, a hotel has been built as well as a station (,) connected to a new railway route ( ) running along the second road.
Here is the map I described:
I guess that I am struggling with this rule: "If a participial phrase is required for the reader to understand the meaning of the sentence, then no commas should be used". I am not sure whether these participle phrases are essential for understanding the meaning.