------a teacher in a university,it is necessary to have at l
2个回答

换个语序就可以了

it is necessary to have at least a master's degree------a teacher in a university

显然应该填to become

这里的to become a teacher in a university 做主语,用becoming应该也可以,但题目中没有这个选项

而CD中都有one,有sb的一般会有for出现,而题中没有,因此只能选A