Be careful not to capsize the boat.

小心不要使船倾覆。

《新英汉大辞典》

We were afraid (that) we were going to capsize the boat.

我们担心会把船弄翻。

《牛津词典》

If a ketch had larger sails than an equivalent sloop, it would heel more (making sailing less efficient) and be more likely to capsize.

如果双桅帆船拥有比同等尺寸的单位帆船更大的帆，它在航行时会倾斜得更多，使得航行效率变低，也更容易翻船。

youdao

They say frightened passengers moved towards one side of the vessel causing it to capsize.

VOA: standard.2009.09.01

Scholars have always been quick to point out that in both cases, This ark, this tevah, is in the words of one scholar "The instrument of salvation through perilous waters" waters that threaten to capsize it, and so blot out God's hopes and plans for his creatures.

学者们总是很快指出在这两个地方，这个方舟，tevah用一位学者的话说就是,“从恶水中获救的工具“,那些要倾覆它的水流，这也体现了上帝的希望和给创造物的安排。

耶鲁公开课 - 旧约导论课程节选

At any moment one of them could split off a chunk more than big enough to capsize a kayak into the 45-degree water.

FORBES: Magazine Article

Rescued were U.S. citizens Jordan Hanssen, 29, and Patrick Flemming, 31, along with Canadian citizens Adam Kreck, 31, and Marcus Pukonen, 30, who were 73 days into the expedition when a rogue wave reportedly caused their 29-foot row boat, theJames Robert Hanssen, to capsize.

FORBES: Rogue Wave Capsizes Trans-Atlantic Ocean Rowers

Ye saw their sails and how the boat was tipping right over till it was going to capsize but it did not, it was just picking up speed because the wind was there and it was good, so they were all sailing great and the boys all shouting, and the men too.

NPR: Excerpt: 'Kieron Smith, boy'