In this paper, we study the Manin triples associated to n-Lie bialgebras.
We develop the method of double constructions as well as operad matrices to
make n-Lie bialgebras into Manin triples. Then, the related Manin triples
lead to a natural construction of metric n-Lie algebras. Moreover, a
one-to-one correspondence between the double of n-Lie bialgebras and Manin
triples of n-Lie algebras be established