How many categories are there in water transport?（）
举一反三
- How many categories does the writer classify into?
- How many product-related factors are there to influence the transport cost? （）
- ______ water is left in the bottle A: How many B: How much C: How
- How many rooftop solar water heaters are there in China currently? How many Chinese companies are manufacturing devices
- How many people are saved from the icy sea water?