Red-crowned cranes fly to Yancheng Nature reserve _______ spend the winter.
The old man lives ___________, but he never feels ___________.
— Do you know mother giant pandas have only one or two babies ___________? —Sorry, I don’t know.
—Is this maths problem ___________? —Yes, I can work it out ___________.
—___________does your sister walk her dog ? — Once a day.
—Would you like to climb the hill with us tomorrow? —If it ___________,I___________.