单项选择题It took me some time to learn the American way of living.选择能替代It took字部分的内容。_____ A、I spent some time learning B、It cost me a lot of time to learn C、I paid some time to learn D、It cost me a lot of time learning
单项选择题多元相关中，m个变数之间的关系是相互联系的关系。 A、正确 B、错误
