答案:I’m not sure the exact date, but it may be two months ago. As I’m a university student, I still have to use pens and pencils regularly, although most of our homework is required to be submitted to my teachers and professors in digital versions. And two months ago, I just experienced my mid-term exams, so I had to use both pens and pencils in my exam. I used pens to write on the answer sheet I and pencils to blacken the corresponding letter of multiple choice on answer sheet II. I remember in case of not enough pens, I bought several pens that time.