a professor and writer [ ] invited to give us a talk about how to study english wella are b is c has d have
问题描述：
a professor and writer [ ] invited to give us a talk about how to study english well
a are b is c has d have
答
b is
a A and B 既是A又是B的同一个人
a A and a B A和B（两个人）
祝你进步
答
a
不是兼的意思，但是题目有很多问题。。
答
b is
一个教授兼作家,是一个人