If you are creating a movie that explains something, it is very common to use B-roll to provide close-ups of the thing you are explaining.

如果生成的电影要解释某个东西，则经常用B卷对要解释的东西提供特写。

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There are various kinds of music: classical, jazz, rock 'n' roll, pop, hip-pop, and R&B, just to name a few.

音乐的类型各式各样，古典、爵士、摇滚、流行、嘻哈和节奏蓝调只是其中一些。

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B: Cut the large piece of dough into many small pieces, roll the dough with a rolling pin into round, thin wrappers.

乙：把面团分成一个个小块儿，用擀面杖把它擀成一个圆而薄的饺子皮儿。

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"If we picked a different year, the B-roll would be Bruno, Spano, Seminiero and Leibell, " said Sen.

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Rossi was there for David, and anything I (or Rash, for that matter) had to say was, at best, B-roll.

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It wasn't a particularly impressive event -- just a single shot in a tiny room supplemented with a bit of b-roll, including a top contender for one of the dorkiest promo videos in the history of the gaming industry.

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