Are you trying to add two columns to one table and one table to another table?

If so you wnat code like

ALTER Table1 add ColA type1 columnConstraints1, ColB type2 columnConstraints2;

ALTER Table2 add ColC type 3 columnConstraints3;

Obviously you have to provide the right tablenames, columnnames, and types, and also the right column constraints (if you want any). And if you add a column with column constraints that include a NOT NULL domain constraint it must also have a DEFAULT constraint (except that if the table is empty when you add the column you don't have to have a default for it if you don't want one).