Parse error: parse error, unexpected T_STRING, expecting ',' or ';' in C:\wwwwhome\test.com\test\default.php on line 17

the content of default.php
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echo '?\';  // one of chinese character
echo '?\';  // here another chinese character
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However, if I put a space after the character, there will not occur error.
ie. echo '?\ ';

Thanks!