战国后期的成都平原,洪水泛滥吞没良田,十年九不收。郡守李冰为治理水患,倡导兴建了水利工程都江堰,改变了成都平原水害、旱灾交织的局面。这一事例说明( )
A ship in harbor is safe, but that’s not ______ ships are built for.
Just as I got to the school gate, I realised I ______ my bank in the cafe.
scientists have learned a lot about the universe, there is much we still don't know.
If you come to visit China, you willa culture of amazing depth and variety.
— Can you come to a party on Saturday, Peter? — Oh, ______I'm already going out, I'm afraid.