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Choose the article "a" or "an". ___ plane.

Choose the article "a" or "an". ___ elephant.

Choose the article "a" or "an". ___ apple.

Choose the article "a" or "an". ___ bear.

Choose the article "a" or "an". ___ ball.

Choose the article "a" or "an". ___ cat.

Choose the article "a" or "an". ___ orange.

Choose the article "a" or "an". ___ train.

Choose the article "a" or "an". ___ umbrella.

Choose the article "a" or "an". ___ book.