October 1, 1949 was the day ________ the People’s Republic of China was founded.
--- Mike, it’s a pity you didn’t come to last night’s concert. It was really great! --- Really? If I ________ so busy, I would have gone with you.
Some children want to challenge themselves by learning a language different from ________ their parents speak at home.
Mathilde and her husband turned the whole room upside down ________ the lost necklace.
________ the help of her teacher, Mary ________ in the past few months.
—Tom has passed the final exam. —______! He never really worked hard before.