Keystone effect
[电] 梯形效应
🧩 词语组成解析
keystone
[['ki:stəun]]
n. 拱顶石, 楔石, 重点
🗣️ 情景例句
I haven't seen you for a long time.
很久没见了。
I worked at the hardware store this afternoon.
我今天下午在五金行工作。
She was wearing a full-length skirt which swept the ground.
身穿一条拖地长裙，