W e will make a brief study on : 1.T he significant events of W orld W ar Two and A merica's entry into it ; 2. The important historical figure of A merican pres id ent ---- Thomas Woodrow Wilson ( 托马斯 · 伍德罗 · 威尔逊 ) ; 3. The Zimmermann Note , and another famous historical event ------4. T he A merican C ivil W ar . Which one is not discussed in the text?