Get line1 and line4 in a repeat pattern file

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1

I have a datafile contain hundreds of lines:

line1
1
2
line4

line1
4
2
line4

line1
3
1
line4

.......

I want data to be:

line1
line4

line1
line4

line1
line4

How can I do this? Please help!

2

nawk -f bobo.awk myFile.txt

bobo.awk:

BEGIN {
  FS=RS=""
}
{
  print $1 ORS $4 ORS $NF ORS
}
3

thanks I will try!

4 
sed -n "/./{p;n;n;n;p;n;p;n;p;}" file