After its invention, it became an almost indispensable part of most households within the space of just a few years.

它在被发明后的短短几年时间里几乎成为了大多数家庭不可或缺的一部分。

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"And also, I react to this as a journalist -- an interchange of information and ideas between government and the news media is indispensable to a functioning democracy, and if you start scaring sources with the possibility of years in prison, the loser is not going to be the news media -- it's going to be the public, " he said.

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Quick, granular feedback from customers is indispensable to a company, which is why we originally developed the Net Promoter system.

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And Chuck recognizes that American leadership is indispensable in a dangerous world.

WHITEHOUSE: The White House