None of us knew what had happened __________ they told us about it.
She _____ great progress in the past 2 years.
His father has worked in this factory _____ he came here in 1980.
The traffic in the city _____ be terrible, but now it has improved a lot. I think you will _____ it soon.
She has _____ this car for nearly ten years.
—In the old days, most teenagers had to work for the landlord (地主) in the field to help _____ their families, because their families couldn’t _____ education for them.—What a pity!