What type of file may have a combination of flat and half-round shapes?

Flat files are designed with a flat surface and varying shapes and sizes for different jobs. The term "flat file" can encompass files that combine flat and half-round shapes, making them versatile for a variety of shaping, smoothing, and finishing tasks. When a flat file has one side that’s flat and the other that’s half-round, it enables users to file both flat surfaces and curved edges effectively.

While a single-cut file typically has only one pattern of teeth for less aggressive cutting, a square file is primarily meant for creating square edges or corners, and a round file is designed specifically for rounding or enlarging holes and creating fillets. Therefore, these options do not include the versatility found in flat files that integrate both flat and half-round capabilities, making flat files the correct answer.