How do you use millimeter in a sentence?

Answer 1

A millimeter is such a small length that it is hard to visualize.

A human fingernail is less than one millimeter thick.

It takes 10 millimeters to make one centimeter, and 25.4 of them to make one inch.

Answer 2

If you spell out the quantity, then you spell out the unit -e.g. "twenty centimetres". If you use figures to indicate the quantity, then you use the use the symbol for centimetres -e.g. "20 cm". Because the centimetre is not named after anyone, it never uses a capital letter -e.g. "centimetre', not "Centimetre".

Answer 3

I measured the pencil with a ruler and it was 150 millimeters long.