Selectional
a. 选择的
🗣️ 情景例句
How much are the dues?
会费多少？
I ought to keep cool.
我应该保持冷静。
When it has been decided where we are going to drill, we put up at the surface an oil derrick.
当确定钻孔地点后，我们就在那里竖起一个井架。