Задайте вопрос.
The little boys have already seen two tigers in the Zoo.
-Who...?
-what....?
-When....?
-Where....?
-How many.....?

- who have seen 2 tigers in the zoo- what the little boys have seen in the zoo- when the little boys have seen 2 tigers in the zoo- where little boys have seen 2 tigers- how many tigers have the little boys seen