"My grandfather works."
Translation:우리 할아버지께서 일하세요.
As they had in the lesson notes, you do not use the honorific to refer to yourself, but also your own. "The honorific suffix -님 (-nim) is affixed to many kinship terms to make them honorific. Thus, someone may address his own grandmother as 할머니 (halmeoni) but refer to someone else's grandmother as 할머님 (halmeonim)." -- Sohn, C. S. (2010), https://en.wikipedia.org/wiki/Korean_honorifics#Honorific_pronouns_and_nouns
The grandchildren use 할배 or 할매 and I am to say 장인 (father-in-law) or 장모 (mother-in-law), nobody mentioning the 님. There is more to it, but I cannot recall what the Korean teacher I met in passing said about this, sorry.
"우리 할아버지" 275, 000 (~99%)
"우리 할아버님" 3, 980 (I'd guess this means the elderly man among us . . .)
why is it 할아버지께서 instead of 할아버님께서 which is how it is in the notes, and in all the other questions on this lesson?