Exercises-Structure Back B. After the war. a character called uncle Sam began appearing in political cartoons His form evolved from an earlier cartoon character called brother Jonathan that was popular during the american Revolution After the war. a character called uncle Sam began appearing in political cartoons, his form evolving from an earlier cartoon character called brother Jonathan that was popular during the American revolution 上一页. Exercises—Structure 上一页 下一页 B. After the war, a character called Uncle Sam began appearing in political cartoons. His form evolved from an earlier cartoon character called Brother Jonathan that was popular during the American Revolution. After the war, a character called Uncle Sam began appearing in political cartoons, his form evolving from an earlier cartoon character called Brother Jonathan that was popular during the American Revolution. Back