span class="keyword">type</span>&nbsp;(<span class="keywordsign">'</span>a,&nbsp;<span class="keywordsign">'</span>b,&nbsp;<span class="keywordsign">'</span>c,&nbsp;<span class="keywordsign">'</span>d)&nbsp;format4&nbsp;=&nbsp;(<span class="keywordsign">'</span>a,&nbsp;<span class="keywordsign">'</span>b,&nbsp;<span class="keywordsign">'</span>c,&nbsp;<span class="keywordsign">'</span>c,&nbsp;<span class="keywordsign">'</span>c,&nbsp;<span class="keywordsign">'</span>d)&nbsp;format6<br>
&nbsp;&nbsp;<span cl