The surface of the earth is still warm even at night. because it heated by solar heat during the day time. No big change is needed. 잘했어요! You wrote this as two sentences. That's okay. But it is not correct to start a second sentence with "because". So, the solution is to write one sentence. The surface of the earth is still warm even at night because it is heated by solar heat during the daytime. Or Because it is heated by solar heat during the daytime, the surface of the earth is still warm even at night.

Great examples, Plrag. My only concern is your statement that it is rare to begin a sentence with "because." Both of the following are complete and correct sentences; the placement of "because" does not matter. Placing "because" at the beginning of a sentence is, truthfully, not rare at all. 1. "Because it is heated by the sun during the day, the surface of the earth remains warm at night." 2. "The surface of the earth remains warm at night because it is heated by the sun during the day." See the following (and link below): "Perhaps some students are told not to begin a sentence with "because" to avoid sentence fragments (something like "Because Mary and Samantha arrived at the bus station before noon" is a sentence fragment), but it is perfectly acceptable to begin a sentence with "because" as long as the sentence is complete (as in "Because Mary and Samantha arrived at the bus station before noon, I did not see them at the station.") " Source: American English (self), http://www2.ivcc.edu/rambo/eng1001/sentences.htm

The surface of the earth is still warm even at night. because it heated by solar heat during the day time. 1) The surface of the Earth remains warm even at night because of the solar energy given off during the day. 2) The surface of the Earth is constantly warm due to the sun's solar energy throughout the day. Just to help you out a little, in English it is very rare you will begin a sentence with 'because'. Other than that, great!

As it is heated by the sun during the day, the surface of the earth remains warm at night. OR Because it is heated... (same). Source: American English (self)

Since sun heats the earth during the day time, the surface of the earth remains warm even at night.