VFP Question

[Ken]

I want to change the value of a field in a FoxPro table,
based on 2 other fields. I have a select that gets me all
numbers that meet condition 1. I then take that list and
go back to the same table to find the pk of the records
that meet condition 2. Since I know the primary key for
each record that I want to change the value, I issued a
Replace Field-21 with 'New Value' Record PK. I get a
syntax error when it encounters the Replace. Can anyone
tell me what I am doing wrong?

Thanks....