I asked my DD7 to finish the sentence A great teacher is... and was told that it is not a complete sentence. :-) So I said well I know that. Please make it a complete sentence by inserting your own definition of a great teacher. Answer - A great teacher is helpful and nice.

DS8 - A great teacher is someone who knows what they are doing. A great teacher should be able to accurately explain things. A great teacher has a lot of knowledge and good teaching skills because that is their job.