或者换言之，引入只读接口作为某些可变种类基类的唯一机会是退回到。NET 2.0，即它们最初被构思出来的时候。

Or in other words, the only opportunity they had to introduce the read-only interfaces as base classes of the mutable variety was back in.net 2.0 when they were originally conceived.

youdao

或者换言之，引入只读接口作为某些可变种类基类的唯一机会是退回到。NET 2.0，即它们最初被构思出来的时候。

Or in other words, the only opportunity they had to introduce the read-only interfaces as base classes of the mutable variety was back in.net 2.0 when they were originally conceived.

youdao