English 英语30.None of us knew what had happened __________ th

English 英语
30.None of us knew what had happened __________ they told us about it.
A.until B.when C.after D.though
31.I think your advice is of great value to me and it’s worth ____________.
A.to take B.taking C.to give D.giving
32._________ is kind ________ you to give your seat to a woman with a baby in her arms.
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