semicircle 

/?sem.i?s??.k?l/

half a circle

n. 半圓形,半圓形的周長,半圓形的東西

We arranged the chairs in a semicircle.

我們把椅子擺成半圓形。

We sat in a semicircle facing the teacher.

我們面對著老師坐成半圓形。

semicircular

/sem.i?s??.kj?.l?r/

shaped liked a half circle

adj. 半圓的

The chairs were placed in a semicircular arrangement.

椅子被擺成了半圓形。

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