Keeping a submarine warm is the easy part; with all of the electronic equipment, electrical systems, and engineering/propulsion systems, it gets pretty toasty, even in Arctic waters. It's keeping everything cool so that systems don't overheat that's difficult.
stay inside stay warm
they stay inside and stay near warm places
Charlie have to walk slowly to school and stay inside during recess in order to stay warm.
Inside - 2007 Cocaine Submarines is rated/received certificates of: Australia:M
Fleas do not die in the wintertime. They either live on animals to keep warm, stay inside buildings, or find other places to stay warm.
Inside - 2007 Inside Cocaine Submarines 4-1 was released on: USA: 10 January 2010
they wear very warm clothing and stay inside their homes
Nuclear Submarines can stay almost indefently for them it is a question of Stores (food). Diesel Submarines are really not designed for under ice operations. AIP Subs can stay submerged for prolonged periods depending on the amount of Liquid Oxygen it has.
Stay inside and keep warm. Do not go outside unless you absolutely must.
They huddle together in a ball to hibernate. The lucky ones on the inside stay warm, but the ones on the outside eventually sacrifice their lives to the cold.
The ice all around you insulates it. Kind of how a dog will bury itself in deep snow to insulate it and keep itself warm.
People mostly stay inside and stay warm and enjoy the holidays and others go outside and shop and do regular winter activities. Kids usually stay outside and play in the snow or they stay inside with their parents. cw: In northern Europe, people get depressed.