谢谢您的link。 Example 2 正说明了我的说法是对的。

William owned and used a house as his main home from 2007 through 2010. On January 1, 2011, he moved to another state. He rented his house from that date until April 30, 2013, when he sold it. During the 5-year period ending on the date of sale (May 1, 2008-April 30, 2013), William owned and lived in the house for more than 2 years. Because it was rental property at the time of the sale, he must report the sale on Form 4797. Because the period of nonqualified use does not include any part of the 5-year period after the last date William lived in the house, he has no period of nonqualified use. Because he met the ownership and use tests, he can exclude gain up to $250,000. However, he cannot exclude the part of the gain equal to the depreciation he claimed or could have claimed for renting the house, as explained next.

没有period of nonqualified use， 这就是说100%capital gain 不用交税。但是depreciation recap不管有没有nonqualified use， 都必须recap and include in ordinary income and subject to the graduated tax rate.