Imperial and impervious

Imperial = pertaining to an emperor or empire
Impervious = haughty, overbearing

Nobody likes him because of his impervious nature.
The imperial glory of England has gone for ever.

Ingenuous and ingenious

Ingenuous = frank, artless
Ingenious = skillful

Everybody likes him because of his ingenuous nature.
The student offered an ingenious solution to the problem.

House and home

A house is a building made for people to live in. A house is built of brick and mortar.
A home is the place where a person (and his family) live. A home is built of love.

The rich man owns twenty houses in the city. (NOT The rich man owns twenty homes in the city.)
Theirs was a happy home, full of love. (NOT Theirs was a happy house, full of love.)

Human and humane

Human = of people
He is, after all, a human being; he can’t be perfect.
She is only human, so give her a break.

Humane = compassionate
He treated his servants in a humane manner.

Ill and sick

Ill means ‘unwell’. In American English, ill is unusual.
She has been ill for one week.

Note that ill is not usually used in the attributive (before a noun) position.

She spent years looking after her sick husband. (NOT …ill husband.)

Sick means unwell in American English.

I am sick.