It’s dangerous to walk across the street carelessly.–You’re right. We can’t be ________ careful while crossing the street.

Do you know why the teacher asks for me ?— He wants you to _____ your absence last night.[ ]

What is your favourite sport—I love ____basketball with his classmate..

There’s no doubt2013will bring more change when the world economy is still unclear.

Do you know Tom, ______ father is an engineer?—- Yes, quite well. He ______ be the first to offer me help when I met with problems.