Explain a electromeric effect , mesomeric …

Inductive effect :It is a permanent effect it depends on the neighbouring group.IT can be +I or -I effect , for example if an electron withdrawing group is attached in a carbon chain
H3C-H2C-H2C-Cl
then it will pull the electron clouds towards itself,although there is no proper losing or gaining of electrons.
Electromeric effect:It is temporary effect which takes place betwen two atoms joined by a multiple bond .This occurs at the requirements of the attacking reagent and involves instantaneous transfer of a shared pair of electrons of the multiple bond to one of the linked atoms.
Mesomeric effect:There are many molecules whose behavior cannot be explained by a single lewis structure , infact the actual molecule is said to be in resonance with its other resonance hybrid .
for example:benzene