This is because only one boat at a time can pass through the narrow channel here, and we must wait for a river steamer going upstream.

原来崆岭滩一条狭窄航道只能过一只船，这时有一只江轮正在上行，我们只好等下来。

youdao

So far as I can see, there is only one boat on the river.

就我所能看到的而言，河上只有一只船。

youdao

This reporter has learned, in fact, only one shrimping boat actually survived the storm.

VOA: standard.other

Only one boat in the convoy had an engine, towing the other two smaller vessels.

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Bahjat is the only one without a boat tied to a dock.

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Glasgow's boat was the only one led by a female skipper.

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