What are the elements that fit neither the metals nor the non-metals called?

1. Metals sit on the left of the table and non-metals on the right. 2. A few elements between them share properties of both groups. 3. Those in-between elements are called semi-metals. 4. They lie in a jagged line separating the metals from the non-metals. _Source: Siyavula Natural Sciences Grade 7 (CC BY 4.0), The properties of semi-metals_