She learned new words and their antonyms.

Please use the emergency stairs in case of a fire.

Due to the earthquake, the city declared a state of emergency.

He wrapped the sandwich in tinfoil.

This rock contains cassiterite.

I have been to Wuxi.

Metallic bonds are formed by ions floating in a sea of electrons.

When he opened the door, a metallic sound echoed.

Alkali metals are very reactive chemically.

Transition metals play an important role in chemical reactions.