— I wonder _________ or not the animal signs are kept in a fixed order.— Oh, they should be.
表示“重要人物”的字母组合是______.
占上中下三格小写字母是______.
下列选项中属于元音字母的组合是______.
I ______believe everything ______ be free in 20 years.
Tara and her sister_____ quiet and they_____ sports.