$$ABCD$$ is the given parallelogram
$$AB=CD$$ ..... (Opposite sides of parallelogram are equal)
So, $$\dfrac{1}{2}AB=\dfrac{1}{2}CD$$
$$AX=CY$$ ...... (as $$X$$ is the mid point of $$AB$$ and $$Y$$ is the mid point of $$CD$$)
$$AX||CY$$ ......... (We know AB||CD, as $$ABCD$$ is the parallelogram)
Quadrilateral $$AXCY$$ is a prallelogram, as a pair of opposite sides is equal and parallel.
So, $$XC=YA$$ and $$XC\parallel YA$$
$$XQ\parallel YP$$ ...... $$(i)$$ (As $$XQ$$ is part of line $$XC$$ and $$YP$$ is part of line $$YA$$)
We have $$ABCD$$ as the given parallelogram
Now, $$AB=CD$$ ....... (Opposite sides of parallelogram are equal)
So, $$\dfrac{1}{2}AB=\dfrac{1}{2}CD$$
$$DY=XB$$ ....... (As $$X$$ is the mid point of $$AB$$ and $$Y$$ is the mid point of $$CD$$ )
$$DY\parallel XB$$ ..... (We know $$AB \parallel CD$$, as $$ABCD$$ is the parallelogram)
Quadrilateral $$DXBY$$ is a prallelogram, as a pair of opposite sides is equal and parallel.
So, $$DX=YB$$ and $$DX||YB$$
$$PX||YQ$$ ...... $$(ii)$$ (As $$XP$$ is part of line $$XD$$ and $$YQ$$ is part of line $$YB$$)
From $$(i)$$ and $$(ii)$$ we get,
$$PXQY$$ is also a parallelogram.