We use the MASU-form, when we speak politely. To make it a negative, we change MASU to MASEN. So, YOMIMASU (to read) becomes YOMIMASEN. To make it into a question, we add the particle KA at the ...

We use the MASU-form, when we speak politely. To make it a negative, we change MASU to MASEN. So, YOMIMASU (to read) becomes YOMIMASEN. To make it into a question, we add the particle KA at the ...