─Forty students in this class?Please tell me something about them.─OK, of them are exchange students,and all these twenty are local students.
Can you help me _______ English?
All the students are talking in the classroom, it’s _________.
—Why are you so tired these days?—Because I have ________ work to do.
—What do you do on Saturday?—I often practice _________ English.
—What do you often do ________ dinner?—I walk with my parents.