He has made another wonderful discovery, _____ I think is of great importance to science.
A devastating(毁灭性的) mudslide in northwest China's Gansu Province earlier in August killed at least 1,467 , with 298 still ___ .
Word has come ___ a 100-million-year-old dinosaur fossil was recently discovered on a mountain in Ningcheng County, Chifeng.
You cannot be more careful when crossing the street, or you may ___ by cars.
Scientists have many theories about how the universe_____.
Teachers required that all the students ___ their homework all alone.