Chris and Jenny sent us some colourful diagrams to show their answers:

Two halvesThree thirdsSix sixthsNine ninths
Julia drew on the line she'd draw to get quarters. Can you see that there are now four identical triangles? (Concentrate on the thickest lines.)
Four quarters
There are lots of ways to divide the shape up into two halves. Sunita and Raj sent us two that they thought were nice:
Two halvesTwo halves