The two old friends were ______ busy _____witheach other ______ the time.— Yes. They haven’t met for long.

John and I will celebrate our fortieth wedding anniversary next month — Oh, ________!

The process of producing electricity may also give out CO2, ______ you heat your house with electricity instead of charcoal

Great changes have taken place since then in the factory _____we are working.

flight was quite late last night.—Yes, it was midnight __________ our planefinally got to Jinan.