Complex sentence: Frustrated by her optimism, Jones storms out of the meeting, but later, after his boss presents him with an ultimatum, he accepts a position on the project, despite his concerns that it may ruin his reputation in the scientific community.
Split into simpler sentences: Frustrated by her optimism, Jones storms out of the meeting. Later, after his boss presents him with an ultimatum, he accepts a position on the project, despite his concerns that it may ruin his reputation in the scientific community.