运行下面的猪脚本时，我在第 4 行遇到错误：如果是，GROUP那么我收到错误。如果我在第 4 行从GROUPTO更改group，则脚本正在运行。组和组有什么区别。

LINES = LOAD '/user/cloudera/datapeople.csv' USING PigStorage(',') AS ( firstname:chararray, lastname:chararray, address:chararray, city:chararray, state:chararray, zip:chararray );

WORDS = FOREACH LINES GENERATE FLATTEN(TOKENIZE(zip)) AS ZIPS;

WORDSGROUPED = GROUP WORDS BY ZIPS;

WORDBYCOUNT = FOREACH WORDSGROUPED GENERATE GROUP AS ZIPS, COUNT(WORDS);

WORDSSORT = ORDER WORDBYCOUNT BY $1 DESC;

DUMP WORDSSORT;