It is hard for him to keep warm by himself.

他自己很难保证自己的温暖。

youdao

By absorbing sunlight, the floating plants help keep the ocean surface relatively warm. When there are fewer of them, the sun's heat concentrates deeper down.

浮游植物由于吸收阳光，有助于保持海洋表面相对温暖。浮游植物较少的地方，太阳的热量会聚集在海洋较深之处。

youdao

By absorbing sunlight, the floating plants help keep the ocean surface relatively warm.

浮游植物由于吸收阳光，有助于保持海洋表面相对温暖。

youdao

Stay in your car and keep warm by running the engine as much as you can.

BBC: UK snow and ice continue to disrupt travel

Heat generated by occupants and computer equipment is caught by heat retention coils to keep the building warm during the winter months.

CNN: Catalog company going lean and green

At least five deaths in the U.S. were blamed on the snowstorm, including an 11-year-old boy in Boston who was overcome by carbon monoxide as he sat in a running car to keep warm while his father shoveled Saturday morning.

WSJ: Northeast trying to get back on track after storm