Anxious refers to being concerned or worried. Eager refers to a strong desire.
Example sentence: Although he was anxious about his upcoming test, Bob was eager to complete it and start his summer holiday.
Regardless vs. irregardless: Regardless is the correct form.
Toward vs. towards: Toward is the correct form
Nauseated vs. Nauseous: Nauseated refers to feeling sick or disgusted. Nauseous means causing sickness or disgust.
Example sentence: Although he considered the judge's actions to be nauseating [disgusting], Bob was unable to attend the rally for the opposing candidate because he felt nauseated [ill].
Arnold, G.T. (2006). The media writer's handbook. McGraw-Hill. ISBN 978-0073526065
Strunk. W. (2007). The elements of style. Coyote Canyon Press. ISBN 978-0979660740
Publication Manual of the American Psychological Association. Fifth Edition (2001). ISBN 978-1557988102