Changes

Put simply, a relation is in 2NF if it is in 1NF and every non-prime attribute of the relation is dependent on the whole of every candidate key.

Suppose your OrderLines table has a Composite Primary Key of OrderID + ProductID. Any other columns in this table that describe Products are only Functionally Dependent on the ProductID, and have nothing to do with the OrderID. These columns are Partially Functionally Dependent on the Primary Key, and should be removed from the OrderLines table and placed in the Products table.