positive: The third plane was flown into the Pentagon, which is a large building near Washington, DC that is the headquarters (or most important building) for the U.S. military.<br>第三架飞机飞向了五角大楼,也就是首都华盛顿附近的大型建筑物,美国军队的总部(或最重要的建筑)。<br>The fourth plane crashed in a field in Pennsylvania, a state that's also in the northeastern part of the country.<br>第四架飞机在宾夕法尼亚州的田野里坠毁,该州也位于美国的东北部。<br>Many people think that the hijackers had wanted to crash that plane into the White House where the president lives, but the people on the plane stopped them from doing that.<br>许多人认为劫机者想要把飞机撞向美国总统居住的白宫,但是机上的人阻止了他们那样做。<br>Almost 3,000 people died in the terrorist attacks that day.<br>那天将近有三千人死于这次恐怖袭击。<br>The attacks had a big effect on the economy, too.<br>这次袭击对经济也有着很大的影响。<br>Many businesses in the World Trade Center and nearby buildings had to close because they had too much damage and they had lost too many employees.<br>世界贸易中心及邻近大厦里的许多企业都不得不关门,因为他们受到了重创,他们损失了太多的雇员。<br>All airplanes were grounded, meaning that they we
negative: 1846年,美国总统波尔克派军队进入两国边境有争议地区。墨方提出强烈抗议,却没有任何效果。4月24日,墨西哥军队与美军发生小规模冲突,打死3名美国人。这一事件正好给美国以开战的借口。5月,美国正式向墨西哥宣战,派出5万军队从陆地和海上侵入墨西哥。墨西哥军队缺乏训练和先进的武器装备,很快就败下阵来,加利福尼亚顺理成章地归并美国。 1848年2月2日,美国与墨西哥签订条约,美国只象征性地支付1500万美元,就得到了包括加利福尼亚、新墨西哥地区在内的近140万平方公里土地。接着,在1853年,美国驻墨西哥公使加兹登又以1000万美元购得美墨边境近10万平方公里土地(后以“加兹登”命名此地)。在这次美墨战争中,墨西哥丧失了大半领土。墨西哥战争之后,美国本土已经比1783年刚刚被承认独立时的领土扩大了两倍。不过,美国扩张道路并没有停止。 国务卿的远见使美国受益无穷 阿拉斯加成为美国领土的过程非常滑稽。