Which sentence is punctuated correctly? she wrote me a letter: and i realized we had a problem. the question is—how can we best our community? i plan to take three items: my journal, a pen, and a camera. his friends include a musician: an actor, and a sports star.

The sentence, “I plan to take three items: my journal, a pen, and a camera.” Is correct. If you would like explaining: the first one is incorrect because they shouldn’t have used a colon, it should have been a comma. The second one is incorrect because they shouldn’t have used a dash, but a colon. The fourth one is incorrect because the colon shouldn’t be there, but a comma. I hope this helps you!

the following key ideas correctly express the key sentence.

restate key idea: most people can learn to swim in ten short lessons.

restate key idea: the majority of water-accident victims require mouth-to-mouth breathing.

restate key idea: an empty, tightly closed gallon jug will support a tired swimmer.  

restate key idea: first aid is to prevent accidents as well as assist in rescue.

explanation: the key idea needs to have the same topic as the key sentence (drowning and safety).