Pls suggest

He is too young for school. First get him accustomed to communicate with other children around. Then better send him to a school where some of his close friends also go. This will give him sense of security. If possible, let him also get close to some teachers before actual admission.

It's a very common problem for a kid of his age and a perfectly normal reaction and you need not be unduly worried about it and remain patient!

its natural.Everything will get O.K after few weeks.If he gets some friends,then they will cry to come from school.

It is a common problem in some children. Please tell our wife to accompany him to school and ask her presence by sitting outside and slowly he will be get involved in the studies and then she can go back to her work (for some days only).