When nobody is the subject, what is the form of the predicate? Nobody knows me

When nobody is the subject, what is the form of the predicate? Nobody knows me

No body, no body, no body, no body

Is some the singular or the plural?
Half of the class are still doing all of the homework because some ( )really difficult.
is/are

It depends on the noun it refers to. If it refers to the plural of a countable noun, then some is the subject and plural. If it is not countable, then plural. Here some refers to home. Home is an uncountable noun, so singular is used

When 3 years is the subject, is the predicate singular or plural?

It depends on the situation
3 years have passed.
3 years is a long time

Olympic Games: singular or plural
Such as the title
I remember doing a few questions, both singular and plural

In the plural
The Olympics is also plural
For example
The 2008 Olympic Games are going be
The Olympic Games have been held each four years
It's usually plural