create an entity relationship diagram

Consider the following business rules: A hospital wishes to construct a database to store current data. It has a number of wards, each of which has a number of patients. A consultant is in charge of only one ward with a ward having only one consultant (except for observation wards which have no consultant assigned to them). Patients can undergo a number of operations. Some consultants perform operations, with operations being performed by only one consultant. Each ward has a number of nursing staff, with nursing staff member allocated to just one ward (unless they are involved in training courses). Create an ER diagram you must state the entity types with their identifiers and all details of relationships (name, degree and relevant membership classes)