Bil
基本脉冲电平（Basis Impulse Level）；基本绝缘电平（Basic Insulation Level ）
🗣️ 情景例句
It was a pleasant surprise.
那是个惊喜。
He that knows not how to hold his tongue knows not how to talk.
不知缄口的不善言。
She works very hard and is very helpful.
她工作非常努力，对同学们帮助很大。