She greeted me with a few words of pleasant welcome in a low clear voice, and I sank into a basket chair feeling distinctly glad that I had accepted John's invitation. 
Her voice was low because she didn't want to be heard by anyone.
mnli hypothesis: Her voice was low because she didn't want to be heard by anyone. premise: She greeted me with a few words of pleasant welcome in a low clear voice, and I sank into a basket chair feeling distinctly glad that I had accepted John's invitation. 