I presumed him to be her husband.

我料想那就是她丈夫。

《牛津词典》

I presumed (that) he understood the rules.

我相信他明白这些规则。

《牛津词典》

I presumed she was the girl's mother.

我猜想她应该是小女孩的母亲。

youdao

The meter would not accept my money at 08:25 in the morning (charging starts at 08:30) and I presumed that the meter was out of order.

BBC: Parking - Your Thoughts

It never upset me because even if former coach Sven-Goran Eriksson was at one of our games, I presumed he was watching someone else and towards the end I never got the feeling he would pick me.

BBC: SPORT | Football | Kevin Nolan column

The Life Story of David Lloyd George - a two-and-a-half hour epic about the UK's leader during World War I - had been presumed lost after it disappeared in 1918.

BBC: Lost Lloyd George film gets showing