1.   For then they disagreed about what their conventions of courtesy really required.

2.   Academics have disagreed for years, though, about whether statistics prove or disprove that belief.

3.   We disagree for two independent reasons.

4.   We disagree for two reasons.

5.   Abraham and Smith have disagreed for years over how to better enforce U.S. immigration and customs laws at border crossings without bottling up traffic.