"Why do you think so?" He suddenly halted his previously fluid pace of speech, paused, and then looked up with a smile at her.
Shi Nian took a deep breath, understanding that he was encouraging her by doing so.
"Because, Professor T, you are exceptionally fond of Room 507."
"Oh?" His interest grew, and he sat up straight, slightly tilting his head towards the bed: "Are you suggesting it’s because I chose to stay in Suite 507?"
Shi Nian’s attention was subtly drawn by Tang Yanqing, so he glanced slightly sideways, and she followed his gaze—then discovered that the sheets on the bed had indeed been changed. Official source is NoveIꜰire.net
Her cheeks flushed, and she quickly lowered her head, gently shaking it: "No. Because you moved into 507... not to investigate a case."
He laughed silently, "Then tell me, what is it for?"
Shi Nian lifted her gaze, her eyes quickly skimming over his face before hastily dropping her head again: "...Right now, we’re analyzing the case seriously. Professor, let’s skip this topic for now, please."
He took a deep breath, gazing quietly at her blush. Then he nodded slowly, "Alright, I won’t digress. You may continue."
Only then did Shi Nian relax, gently narrowing her eyes, lifting her head, and returning to her thoughts.
"The reason I say you have a special fondness for 507, Professor, is because your behavioral analysis class has a very high threshold, and the twenty seats require your personal interview. But it so happens that all the members of Suite 507 were lucky enough to be selected as your students."
Tang Yanqing smiled and nodded, "But perhaps it also suggests that the members of 507 just happen to have a talent for behavioral analysis?"
Shi Nian shook her head, "If you say it like that, Professor, it would be just as well to attribute it to S. Because she admires you, it’s inevitable that when she returns to the dorm, she’d embellish her descriptions of your class to her roommates. And being the queen, effectively the ruler of the suite, Marina, Zhong Kui, and even Jack, who secretly admires her, would be influenced by her and thus all sign up for your course."
"If you say it this way, Professor, it would be easier to deceive people."
"Ha..." He chuckled, "Alright. If anyone notices my special fondness for 507 in the future, I’ll use your explanation. After all, S is no longer here, and there’s no way to verify."
Shi Nian did not laugh, "Professor T, you never do anything without a reason, so I think your purpose in doing this is because the suspect’s informant is in Room 507. You made all the members of 507 your students to conveniently observe them closely, inside and outside of class, looking for clues."
Tang Yanqing slowly crossed his legs, leaned back slightly, and looked at her with a serious expression.
Seeing this posture, Shi Nian almost couldn’t help but feel [awed] or [admiring]. She blushed and quickly waved her hand, "Showing off in front of an expert, forgive my presumption."
He laughed, clapping gently, "Impressive, you saw through me."
Shi Nian, blushing, quickly asked, "Then, after observing for such a long time, Professor, do you already have someone in mind?"
Tang Yanqing, however, changed the subject, "Tell me about your Little Pearl. It was the homework I left you before we parted a month ago."
Shi Nian felt a small sting of frustration, then earnestly said, "During that month, I truly studied some knowledge about pearls. I learned that pearls have a ’lifespan,’ roughly living for about 100 years."
"The reason." He listened quietly, sitting upright, leaning back against the chair. The light reflected on his black-framed glasses, exuding a strong scholarly and rigorous demeanor.
Shi Nian calmed herself accordingly.
"From a chemical perspective, pearls are organic gemstones, and their luster comes from the surface ’nacre layer.’ Over 90% of the nacre layer is calcium carbonate, along with a small amount of organic matter, trace metal elements, and tiny droplets of water."
"However, the ’nacre layer’ is very unstable, and over fifty to sixty years, the minute droplets in the nacre layer will evaporate, causing the pearl to gradually lose its luster, even drying and crumbling to powder. Thus, ancient pearls generally have little chance of being passed down to the present day."
Tang Yanqing nodded and didn’t speak, but glanced at the laptop.
Shi Nian frowned, understanding that his subtle expression suggested her answer was incomplete. He was almost tempted to open his notes to show her.
She took a deep breath, "In China’s context, it’s even more complicated. Because within the scope of traditional Chinese medicine, pearls are also used medicinally, for calming the mind, clearing the vision, and enhancing beauty. So many pearls were later crushed into pearl powder, incorporated into medicines or made into beauty applications."