—It’s smoggy these days. That’s terrible!—Yes, I hope to plant trees. ______ trees, ______air pollution.
English will help us ______ in our work and study.
—What can you see on the table? –We can see four ___ and six ______.
I didn’t go to bed _______ ten o’clock last night.
The room isn’t big enough for us ________.
This is _______ English class. I hope you can enjoy English.