1) His sister is beautiful. ;-)
HIS SISTERS ARE BEAUTIFUL.
2) What color is this flower? -It's red ;-)
WHAT COLORS ARE THESE FLOWERS? - THEY'RE RED.
3)She is a tall gymnast ;-)
THEY ARE TALL GYMNASTS.
4)Is your bag light or heavy? ;-)
ARE YOUR BAGS LIGHT OR HEAVY?
5) What's that? - It's a bench ;-)
WHAT ARE THOSE? - THOSE ARE BENCHES.
6)He has an oval face;-)
THEY HAVE OVAL FACES.