Make sure it's clean river sand, not beach sand.
确保那是干净河沙，不是海滩的沙子。
If you swim in a river or lake, be sure to investigate what is below the water surface.
如果你在河里或者湖里游泳，一定要弄清楚水面下有什么。
Be sure not to go swimming in this river.
务必不要到这条河里去游泳。
Are you sure we can cross the river safely?
你确信我们可以安全地过河吗？
Are you sure we can cross the river safely?
你确定我们可以安全地过河吗？
Desk cledc: Sure. We have a one-day trip along the river. lt's quite beautiful.
接待员：好的，我们这里有沿河一日游，很漂亮的。
Desk cledc: Sure. We have a one-day trip along the river. lt's quite beautiful.
接待员：好的，我们这里有沿河一日游，很漂亮的。
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