短语词组短语depressed semicircle 扁半圆Halbkreis semicircle 半圆semicircle key 半圆键navigable semicircle [气象]可航半圆open semicircle 开半圆SEMICIRCLE PATRN 半圆图案;珠网叶子贴图材料left semicircle 左半圆 返回 semicircle