His behavior became a good model for us.

He is a fool, acting without thinking.

This train is running on the main line.

This game is ideal for learning the basic rules.

I was surprised by his full-blown cooking skills.

Kaku is my best friend.

He is proficient in calculating quadrature in astronomy.

He is struggling to understand the ablative case in Latin.

The sum of one angle of this triangle and its complementary angle is 90 degrees.

I have confirmed your reservation.