That is a generalisation, as there have been effects since the silents in 1900. But there was no special effects industry and effects-driven movies were rare.

那只是一种大概的说法，因为早在1900年，还是无声电影时代时就有特技了。但那时没有特技效果工业，而且使用特技的电影还很少。

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We watch the world respond to the silents, an unsettling new phenomenon.

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Until then, I suggest that you seek out a copy of "In the Spirit of Jazz, " a wide-ranging essay collection that contains seven of his best pieces about film (14 more of which can also be found in Philip Lopate's "American Movie Critics: An Anthology From the Silents Until Now").

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But, starting in the nineteen-thirties, music soundtracks were added to silents, and the films needed to move through the projector at twenty-four frames a second, so that the optical sound reader could handle the music track.

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