I'm not sure if I should share a bed with him.

I haven't decided yet whether to share a bed with him.

We are classmates from the same university.

He was trying to kidnap the child.

I don't know whether he used sweet words to tempt me or not.

That's exactly as you say.

Rare earth elements are essential materials for the manufacture of electronic devices.

Hydrogen is the most abundant element in the universe.

Transition elements play an important role in chemical reactions.

Oxygen, which is one of the chemical elements, is necessary for us to breathe.