I want to split a file into chunks with 2 words each.$cat tmpword1 word2 word3 word4 word5 word6 word7$sed -e 's/word. word. /&\n/g' tmpword1 word2 word3 word4 word5 word6 word7$sed -e 's/word. \{2\}/&\n/g' tmpword1 word2 word3 word4 word5 word6 word7I expected the last command to give same result as the one before it. What is wrong? 
sed match pattern N times
text processing;sed