They had to keep adding sails to make the junk sail in a straight line.

他们不得不添加风帆，这样才能使帆船直线行驶。

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Next they hop on a traditional junk for a sail across Halong Bay, whose waters teem with prawns, oysters, squid and snapper that are staples of the local cuisine.

CNN: Exotic culinary tours around the world