Was built during March 1930 through May 1931
A dependent clause. Because this sentence only give an action, there is no cause for this action unless given said cause.
Melted plate material reappears by way of volcanoes
Answer: In memorable phrases, he envisioned a better future, founded upon four freedoms: the "four essential human freedoms," some traditional and some new ones. The four freedoms he outlined were freedom of speech, freedom of worship, freedom from want, and freedom from fear.
Explanation: I think this might help you.
This is a run on sentence because it’s combing two sentences without a .