  Based on the recently precise measurements of the electron-positron
annihilation reactions into a neutron and anti-neutron pair by BESIII
collaboration, the effective form factor of neutron was determined in the time
like region, and it was found that the effective form factor of neutron is
smaller than the ones of proton. The effective form factors of neutron shows a
periodic behaviour, similar to the case of proton. Here, a compared analysis
for $\Lambda$, $\Sigma^0$ and $\Xi^0$ is performed. Fits of the available data
on the effective form factors of $\Lambda$, $\Sigma^0$ and $\Xi^0$ with charge
zero, allow to show a universal phenomenon of the oscillation behavior in their
effective form factors. However, this needs to be confirmed by future precise
experiments. Both theoretical and experimental investigations of this
phenomenon can shed light on the reaction mechanisms of the electron-positron
annihilation process.
