Welcome to the Science Museum, everyone! This stone axe _______ in South Africa and experts can’t be exactly sure about its use.
The birth rate in a city___to fall as its Cross Domestic Product(GDP)rises steadily
—Do you mind if I open the window? —____I feel a bit cold
When people want to relax themselves,they prefer___TV or listen to music rather than___newspaper
Were it not for the snowy weather,we___all right
Thank you for giving me a hand.I___in the experiment without your valuable help