DevOps, CI/CD and Automation

I created a script as follows:

alter table aa
drop (cola, colb, colc);

alter table bb
drop (cola, colb, colc);


I get an error that I need ";" or "/" after drop. I don't understand the need for this. Can anyone give me the syntax to drop multiple columns from multiple tables. And what is the syntax for adding multiple columns to multiple tables?

I had tried the following for about 50 tables. It looked like it worked for about 5 tables, then it aborted.

alter table aa
add (cola char(1), colb char(1));