you must need 183 days in 2009

Must 183 plus In 2009. Don't need use 2007. As inpub 519. (China for 2 & 3)

Even if you meet the substantial presence test,you can be treated as a nonresident alien if you:
1) Are present in the United States for less than 183 days during the year,
2) Maintain a tax home in a foreign country during the year, and
3) Have a closer connection during the year to one foreign country in which you have a countax
home than to the United States (unless you have a closer connection to two for-eign countries, discussed next).