I was just falling asleep ____ there was a loud knock at the door.
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.