—Are these your English books? —Yes, ________.
----I think it’s impossible for us to work out the plan in just two days. It’s too difficult.----You’re right. We can’t be _______ careful and hard while working on it.
The teenagers usually have many problems at school, and they don’t know ________ them, so we should give them some help.
Wearing blue clothes can make ______ easier to feel less stressed. I will wear a blue T-shirt today.
----Would you like some coffee or tea?----________. I prefer a glass of water.
Mr. Sun has devoted most of his time _______ his teaching work.