前面加冠词an，例如：
1.That looks like an interesting book.那好像是本有趣的书。
2.There was an interesting sequel to these events later in the year.这几件事发生以后，当年就出现了一种有趣的结果。
3.She gave an interesting talk on her visit to China.她做了个关于她在中国访问的有趣报告。
凡事以元音音素（不是指元音字母）开头的单词前面要用冠词an，以辅音音素开头的单词前用冠词a，因为interesting是元音音素开头的，所以用an
