Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_12591022_2 (teaching_language VARCHAR, duration__years_ VARCHAR)

### Question ###
What is the teaching language with the duration (years) 3.5?

### Accurate SQL ###

SELECT teaching_language FROM table_12591022_2 WHERE duration__years_ = "3.5"