Firstly, let me point out that some people may think it odd that there are corrections being made to a post written by an English teacher. I just want to say that we strive to ensure that all posts written by native speakers/teachers are written correctly so that learners know that they can trust that what we write is (almost certainly) correct.
In answer to your question, I wish I knew the answer. I always teach the full infinitive form "To be" etc, but the only child I taught in Spain had a course book in which every verb was shown in the bare infinitive. I stuck to that pattern with him because that was how he was being taught at school and I didn't want to confuse him. I don't know what current TEFL/TESOL teaching practices dictate as I am now only involved in conversation classes and "Use of English" with my private students.