What is the different between 이다 and 있다?

Which sentence is in the subjunctive mood? you don’t usually arrive on time. are you planning to arrive on time tomorrow? i insist you arrive on time tomorrow. come on time.

How does tan build a central idea of her story in the excerpt? tan discusses the types of questions on achievement tests to support the idea that the tests limit students' ability to write well tan explains a question on a language achievement test to support the idea that the tests shd d include more interesting content tan gives an example of her experience with achievement tests to support the idea that they are not always accurate measures of language ability tan considers how her mother might answer a question on a test to support the idea that nonstandard english limits a person's ability to communicate

Which is the correct definition of an economy ?