Perithallium
围层
🗣️ 情景例句
because the doctors and nurses are so busy?
因为医生和护士们都非常忙？
Their grandchildren are grown up now.
他们的孙子现在长大了。
and they provided a striking demonstration of the potentialities hidden in instruments and apparatus.
并充分显示出了仪表和仪器的潜在力量。