其它
If three couples stand in a row for taking a photo, how many ways are there for only one couple to stand next to each other? 
Overseas Competition->Knowledge Point->Counting Modules->Statistics and Probability
$$\_{3}C\_1\times \_{2}C\_1\times \_{3}A\_3\times \_{2}C\_1=72$$,  $$\_{3}C\_1\times \_{2}C\_1\times \_{3}A\_3\times \_{2}C\_1\times \_{3}C\_1=216$$,  $$72+216=288$$. 