вы можете использовать awk
$ cat file
mark1 dsf
abc
def
before mark2 after
blah mark1
ghi
jkl
mno
wirds mark2 here
pqr
stu
mark3
vwx
yz
$ awk -vRS="mark2" '/mark1/{gsub("mark1.*","")}/mark3/{ gsub("mark3.*","");print;f=1 } !f ' file
after
blah
here
pqr
stu