Get rid of jxl with grep、awk、head、sed

[root@xilong startimes]# cat >>/startimes/xilong.txt <<EOF
> lwz
> ylz
> ckc
> jxl
> EOF
[root@xilong startimes]# cat xilong.txt 
lwz
ylz
ckc
jxl
[root@xilong startimes]# grep -v "jxl" xilong.txt 
lwz
ylz
ckc
[root@xilong startimes]# head -3 xilong.txt 
lwz
ylz
ckc
[root@xilong startimes]# sed '4d' xilong.txt 
lwz
ylz
ckc
[root@xilong startimes]# sed '/jxl/d' xilong.txt 
lwz
ylz
ckc
[root@xilong startimes]# awk '/jxl/' xilong.txt 
jxl
[root@xilong startimes]# awk '!/jxl/' xilong.txt 
lwz
ylz
ckc