使用awk

awk '{split($2,a,",");for(i in a)print $1"\t"a[i]}' file

将第二列分割为逗号，然后为每个分割值打印第一列和该值

Splits the second column on commas and then for each split value, print the first column and that value

也在sed

sed ':1;s/\(\([^\n]*\t\)[^\n]*\),\{1,\}/\1\n\2/;t1' file