A straightforward explanation that includes examples on the subject of oil spills in Alaskan waters clarifies singular and plural subject-verb agreement. Then your charges identify whether the subject and verb agree in six sentences. After that, they select the correct form of the verb (from two choices) in each of 12 sentences. Next they write in the correct form of the verb of their choice in six more examples. A nine-item Review and Assess section sums it all up.