His plan has a flaw.

He looked up at the tower.

We made a new plan.

We are planning a picnic for next week.

He calculated the area of the triangle.

He is good at solving trigonometry problems.

Let's compare these two products.

She has difficulty listening to music due to a problem with her auditory organ.

He drew a triangle on the blackboard.

She is learning how to use the comparative in English.