alter table adding multiple columns

[phpprogrammer]

Dear Friends,

In mysql we can alter a table (add columns) in the following syntax

alter table tablename add column column1 columntype, add column column2 columntype,add column column3 columntype,-----------------,add column columnN columntype

how can we do it in pgsql

ie how can I add multiple columns to a table in pgsql

regards,
bvsureshbabu