Need Help for Errors

Hi Sir,

I am getting the following errors in my website when i validate it.
Please can you help me with this.
Need you advice.

Validating http://www.profileleadercorp.com/
Error [108]: "there is no attribute id"

Validating http://www.profileleadercorp.com/
Error [108]: "there is no attribute role"

Validating http://www.profileleadercorp.com/
Error [108]: "there is no attribute placeholder"

Validating http://www.profileleadercorp.com/
Error [108]: "there is no attribute class"

Validating http://www.profileleadercorp.com/
Error [76]: "element "nav" undefined"

Validating http://www.profileleadercorp.com/
Error [76]: "element "header" undefined"

Validating http://www.profileleadercorp.com/
Error [76]: "element "footer" undefined"

Validating http://www.profileleadercorp.com/
Error [76]: "element "aside" undefined"

Thanks & Regards
Russel