Student or Learner
Molotov sees the West as deceitful, breaking its promises made at the previous meetings two years ago, which had united the three Allies against Nazi Germany.
Why is the "breaking its promises made at the previous..." part set off by commas?
Participle phrases use no comma if it's describing a noun that immediately precedes.
They need a set of commas ONLY if it's in the middle of a sentence.
I wonder why there is a comma after "deceitful."
Thanks in advance.
It appears to be in the middle of a sentence.
There is a pause needed between "deceitful" and "breaking..." The pause lets the reader/listener know that the phrase is helping to define what is felt to be "deceitful."
Without the comma, the listener/reader will think that "deceitful" is modifying "breaking" rather than the West.