改错：Being a teacher,he used to stay up far deep into the night。

As a teacher,he used to stay up far deep into the night.
As 在句首加名词短语是一种习惯性的用法 Being一般很少用

暂时找出两个错误：

1.be used to doing sth 习惯于做某事
这道题考察了这一个短语

2.deep应该是副词形式。

所以正确句式应该是：
Being a teacher, he's used to staying up far deeply into the night.

deeply

副词形容stay up动词

As a teacher,he used to stay up far deep into the night.