The lad fell backwards, landing on his backside.

那个男孩向后倒下去，屁股着地。。

《柯林斯英汉双解大词典》

You'll get a smack on your backside if you're not careful.

要是不小心，就打你的屁股。

《牛津词典》

On the first day of Mr Sannikov's, many police witnesses failed to turn up, and one claimed a bruise on his backside had briefly put him in hospital.

Sannikov的审讯第一天，许多警界证人未能出席，有一位声称自己因背部瘀伤而短暂入院。

youdao

"We are at 100 percent of our planning level in terms of protection of Gulf islands,national seashore, to protect predominantly the wetlands and estuaries and sea grass beds that are on the backside of the islands."

VOA: standard.2010.05.26

And instead of trying to do things differently on the backside of my career, why not focus on the things I do well, and try to be very good at that?

WSJ: Teixeira Knows His Limits

Harassed at every turn and dropped on his backside more than once, Tavares skated through 17:03 of fruitless ice time against a team intent on showing it's serious about its defense after getting embarrassed in a first-round loss to Philadelphia a year ago.

WSJ: Physical Penguins defense rattles Islanders

On the backside of the new snacks, you'll soon find his fortune-cookieish maxims about exercise.

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