We work together to achieve our common purpose: ________ world that is safer, cleaner and healthier than ________ one we are living in.
We may meet all kinds of difficulties in the future, but we should be confident enough toany challenge.
Millie is quiet and modest and easy________________.
She has finished typing but she doesn’t know _______ next.
The kind teacher devoted all her time she had ___________ her students.
— It’s dangerous to walk across the street carelessly. — You’re right. We can’t be careful while crossing the street.