I've worked for 〇 years at this company, and 〇 years in this department.
This is my 〇th year at this company, and 〇th year in this department.
「入社○年目で、この部は○年目です」は英語で「I've worked for 〇 years at this company, and 〇 years in this department.」と言います。また「〇年目」を中心したいなら「This is my 〇th year at this company, and 〇th year in this department.」です。
入社4年目で、この部は2年目です。
This is my 4th year at this company, and 2nd year in this department.
I've worked at this company for ten years, and this will be my fourth year in this division.
I've been here for ten years, and three years in this section.
ーI've worked at this company for ten years, and this will be my fourth year in this division.
「この会社で10年間働いていて、この部署では4年目になります」
to work at ... で「…で働く」
for ten years で「10年間」
fourth year で「4年目」
division で「部署」
ーI've been here for ten years, and three years in this section.
「ここ(会社)には10年間、この課には3年います」
section で「部・課」
ご参考まで!