nText doesn't allow insert of variable tyoe String

[JennyPeters]

I'm trying to insert the value for a string type variable called 'strCommets' into a table field called 'comments' that is of the type 'nText'. I keep getting an error that says:
'Application uses a value of the wrong type for the current operation'

If I can't insert a String into a nText, then what varialbe type can I insert into a nText?

Thanks,
Jenny