He understands the importance of learning.

He is majoring in psychology.

Gaku is my best friend.

He has a deep interest in archaeology.

An antiquark is the antiparticle of a quark.

An antiparticle is a particle that pairs with a matter particle.

He invented an anti-gravity device.

He opposed the plan.

He was surprised by the recoil of the gun.

He was expelled from the party because he took anti-party actions.