23. Everybody _____ in the hall where they welcomed by the secretary. A. assembled B. piled C. joined D. accumulated
<assemble>assemble (人群)聚集assembly line 装配线 semblance 外表resemble 相似，相像take after 与某人长得像</assemble>
<pile>pile 堆积compile=put together 编辑，汇编</pile>
<accumulate>accumulate 积累cumulus 积雨云cumulative 积累的，渐增的</accumulate>