Has vs Had: Choosing the Right Form
先写下记得的内容，再查看解释。不要填写个人信息。
查看解释
As main verbs, has and had describe possession, experiences, relationships, or schedules. She has an apartment describes a present connection with the apartment; she had an apartment puts that connection in the past. Neither sentence alone proves that she lives or lived there. As helpers, has forms the present perfect and had forms the past perfect.
Our clinic has three general physicians on duty each morning.