No, you guys are not writing proper Mandarin.
Correct ones:
Äã?Uuml;ÃÀ¡£ ÎÒÊÇÒ»¸öÓ?Ccedil;®µÄÃÀ?uacute;ÈË¡£
To view this in IE, click View-Encoding-Chinese Simplified (GB2312).
If you want to write it in English alphabet, Ni3 hen3 mei3. Wo3 shi4 yi2 ge4 you3 qian2 de mei3 guo2 ren2.
Edit: It seems the forum doesn't accept the Chinese language.