"I called in sick yesterday and said I had a cold."
"I chucked a sickie yesterday."
- "Yesterday, I had the day off due to a cold."
"I had the day off" 「会社を休んだ」
"due to a cold" 「風邪で」
- "I called in sick yesterday and said I had a cold."
"to call in sick" は体調が悪いので会社に電話して休む許可をもらうということです。
"said I had a cold" 「風邪引いたと言いました」
- "I chucked a sickie yesterday." はオーストラリアだけかもしれないですがネイティブな言い方です。嘘をついて会社を休む。
Officially, I was out sick yesterday.
On paper, I called in sick yesterday.
Technically, I was “sick” yesterday.
I told work I was sick yesterday.
As far as work knows, I was off sick yesterday.
「〜ってことになっている」は英語だと、
officially（公式には）
on paper（書類上は／建前では）
as far as X knows（Xの知る限りでは）
technically（形式上は／一応は）
で表すのが自然です。
オーストラリア 
アメリカ合衆国 
