"Dr. Kim's new theory challenged everything scientists had believed for decades. While some applauded her courage, others fiercely criticized her work, calling it unproven and dangerous."

"The artist spent three years on the painting, correcting every tiny detail again and again until each brushstroke was exactly right."

"Teenagers today spend an average of seven hours per day on screens. This constant exposure affects sleep quality, shortens attention spans, and reduces face-to-face social interaction. Experts agree that setting daily screen-time limits can significantly improve teenagers' mental and physical health."

"The town had not seen rain in four months. Farmers watched helplessly as their crops withered. The local government issued emergency water restrictions, and residents were asked to avoid watering their gardens."

"Marie Curie won the Nobel Prize twice — first in Physics in 1903, and again in Chemistry in 1911. She remains the only person to have won Nobel Prizes in two different sciences."

"The team of researchers ______ been working on the project for two years."

Original: "When Mia talked to her teacher, she was very nervous."

"Many students find mathematics difficult. ______, with regular practice and good study habits, most students can improve significantly."

"(1) Climate change poses a serious threat to biodiversity worldwide. (2) Rising temperatures cause habitats to shrink, forcing many species to migrate or face extinction. (3) My favorite animal is the polar bear. (4) Scientists predict that one million species could be at risk by 2050 if no action is taken."

"The wind whispered secrets through the old oak trees."

"Every year, millions of tons of plastic enter our oceans. Sea turtles mistake plastic bags for jellyfish and die after consuming them. Seabirds feed plastic fragments to their chicks, causing starvation. We must ban single-use plastics immediately before it is too late."

"Despite years of preparation, the athlete stumbled at the finish line and finished last. His dreams of a gold medal shattered in seconds. The crowd fell silent, unsure whether to applaud his effort or mourn his defeat."

"Over the past century, the average global temperature has risen by approximately 1.1°C. While this may seem insignificant, scientists warn that even small temperature increases can trigger massive changes. Glaciers are melting, sea levels are rising, and extreme weather events are becoming more frequent. ______, the economic cost of inaction far exceeds the investment needed to transition to clean energy."