Here are a few ways to continue the sentence, depending on the intended meaning:

1. **"The doctor phoned the nurse because she was late, and the patients were already waiting in the examination rooms."**

2. **"The doctor phoned the nurse because she was late, wanting to make sure everything was alright."**

3. **"The doctor phoned the nurse because she was late, and the morning shift had already begun without her."**

Note that the sentence contains an **ambiguous pronoun** — "she" could refer to either the doctor or the nurse. The continuation can help clarify which person was late depending on the context added.
