The opening theme is taken up by the strings.

开始的主旋律由弦乐继续发展。

《牛津词典》

Already from the very opening lines we see in this a clue to the theme that is going to follow.

打从一开始,我们即看出这条线索,连系到即将发生的主题。

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The company says it is on track for the late 2015 opening of its planned theme park in Shanghai.

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In January Stern debuted on Sirius, opening his show with the theme song from 2001: A Space Odyssey--accompanied by flatulence.

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And then there's Sony Pictures Television, which sent out a Joan of Arcadia box that not only played the series' theme song upon opening, but also featured a live tree, which was prominent in the provided episode.

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