The sum of the two numbers is seven.

Let me sum up the main points of the presentation.

He received a lump-sum payment when he retired.

I made a lump sum payment for my car.

I made a lump-sum purchase of all the furniture for my new apartment.

Sumac is a type of flowering plant that belongs to the cashew family.

Sumach is a type of tree in the cashew family.

Sumatra is the largest island in the Malay Archipelago.