With the heart pounding in her chest, and a big smile on her face, she put another self-sticking IV in Mieczyslaw's arm.
Her smiling face belied the thrill she was feeling at applying the IV.
mnli hypothesis: Her smiling face belied the thrill she was feeling at applying the IV. premise: With the heart pounding in her chest, and a big smile on her face, she put another self-sticking IV in Mieczyslaw's arm.