gistfile1.txt

Get:93 http://cn.archive.ubuntu.com precise/main Translation-en [726 kB]                                  
98% [86 Packages bzip2 0 B] [93 Translation-en 250 B/726 kB 0%] [87 Packages 748 B/2,179 B 34%]           
bzip2: Data integrity error when decompressing.
	Input file = (stdin), output file = (stdout)

It is possible that the compressed file(s) have become corrupted.
You can use the -tvv option to test integrity of such files.

You can use the `bzip2recover' program to attempt to recover
data from undamaged sections of corrupted files.