1 anything interesting不是倒装,因为： 疑问代词/ 疑问副词 + 形容词.-------形容词必须写在後面,又如：what else , nobody brave enough
2 interesting books -------形容词 + 名词-------形容词必须写在前面

3 He didn't buy anything that day / he bought nothing that day
-------- 倒装句： Not anything did he buy that day //Nothing did he buy that day.
原理：否定词（不是主语）开头：not anything / nothing .