1. This led to the construction of earthen or stone steps, arranging the audience into a semicircle in front of the speaker. 这导致了泥土阶或石阶的建构，安排观众们面对讲演者坐成一个半圆形。
2. Cut the circular cake in half and set each semicircle against adjoining sides of the square to form the top of the heart. 把圆形蛋糕切成两半，把每个半圆放在正方形的两边，形成心形的顶部。
3. We sat in a semicircle round the fire. 我们坐在炉火前，围成一个半圆形。
4. They sit cross-legged in a semicircle and share stories. 他们盘着腿围成半圆坐在一起讲故事。
5. He indicated a semicircle with a radius of about thirty miles. 他标示出一个半径大约三十英里的半圆。
