It is to solve some of the problems of life, not only theoretically, but practically.
它不仅要从理论上解决一些我们生活中的问题,而且要在实际生活中解决问题。
It should be pointed out that your proposals are theoretically correct but practically impossible.
应该指出你们的建议理论上是正确的,但在实际中却是行不通的。
Theoretically, this is possible, but practically, such a system would not be something a consumer would buy.
虽然理论上是可能的,但是消费者不会购买这样的系统。
应用推荐