Write the words.  按要求写单词。

weak（同音词）                   one（序数词）                  play（名词）                   brush（复数）               

throw（反义词）                 want（第三人称单数）                   eat（过去式）               

sun（形容词）                     shop（过去式）                             heavy（比较级）                 

组播路由协议可分为域内组播路由协议和______两大类。