________ twice a year, whether it is a car or a bus or a truck, is the rule that every driver must obey in this city.
Generally speaking, prices of daily goods ______ through the Internet are lower than store prices.
The young man invited the lady to dance with him, but she ______ his invitation.
-- What’s your plan for this winter vacation? -- I’ll take an express train to Dalian for my holiday ______ school ends.
---Where did you get to know her? --- It was on the farm ______ we worked.
I want to buy that kind of cloth because I ______ the cloth ______ well.