硬

I felt something hard pressing against my side.

To be turned into iron, the metal itself must be strong.

inflexible plastics

stiff collar/brush/cardboard

hard bed/mattress

He will never pay up unless you get tough with him.

Kid-glove methods haven't worked—it's time to get tough.

be hard-hearted

be stiff in manner; harden one's attitude

steel one's heart

Some beggar children cornered us for money.

He foisted his company on us.

manage to squeeze ten pages of text out of one small incident

The trademark is prestigious.

have masterly skills

quality products/goods