1.Explanation: On Valentine's Day (ET) the Sun unleased one of its most powerful explosions, an X-class flare.
解释：就在情人节这天（美国东部时间），太阳释放了它最具力量的爆炸之一——一个X级的耀斑。
2.The house had been unleased for a year.
那楝房子整整一年没有租出去。
3.No wire forming part of the system shall cross any street or unleased Government land.
任何组成该系统一部分的导线不得横过任何街道或未批租政府土地。