Jack has learned more about teamwork ________ he joined the soccer team.
A.until B.since C.while D.though
I like dancing, ________ I don't have enough time to practice it.
The train was late, ________ we had to wait for half an hour.
Study hard, ________ you may catch up with your classmates soon.
Stop cutting down trees, ________ the earth will become worse and worse.
Hold your dream, ________ you might regret some day.
A.and B.or C.but D.so
