这两天用find命令老是碰到这个问题：

[user@dev-test git-1.7.6]$ find /usr/include/ -name *.h | xargs grep
find: paths must precede expression
Usage: find [-H] [-L] [-P] [path...] [expression]
Usage: grep [OPTION]... PATTERN [FILE]...
Try `grep --help' for more information.

是哪里错了？