9. Everybody______ in the hall where they were welcomed by the secretary.
A. assemble B. accumulated C. piled D. joined
<accumulate>
accumulate 积累
gather 收集(到一起)，收割(庄稼)
collect 收集(带有某种目的的收集)
</accumulate>
<pile>
pile 堆到一起
compile 汇编，编辑
pilgrim 圣徒，朝圣者
analog 类比，类似物
analogy 类推
</pile>