Most Americans start to school at the age of five when they enter kindergarten(幼儿园). Children do not really study at this time. They only attend for half the day and learn what school  is like. Children attend elementary school for the next six years. They learn to read and write and work with numbers. They also study the world and its people. After they leave elementary school, children go to junior high school for three years and senior high school for another three years. This is called secondary education. In some places, the children go to elementary school for eight years and high school for four. In all, elementary and secondary education together take twelve years to complete excluding （不包括）kindergarten.
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The elementary and secondary education together take the children ____ to complete in the USA.
A. thirteen years     B. nine years
C. twelve years      D. eleven years
Most American children enter kindergarten _________ .

A．at the age of five	B．to study two years
C．to learn science	D．about two years old

In elementary school they should stay there ________ .

A．for six years	B．for three years
C．for another three years	D．to study hard

Children should study how to __________ .

A．act

B．become an astronaut

C．read and write

D．read, write and work with numbers

Some American children have their elementary school education for ___ .

A．five years	B．four years
C．eight years	D．seven years