Write the plural form of the following nouns.

Here are the plural forms: country -> countries, saleswoman -> saleswomen, match -> matches, boy -> boys, sister-in-law -> sisters-in-law, man -> men, tooth -> teeth, handkerchief -> handkerchiefs/handkerchieves, potato -> potatoes, deer -> deer, piano -> pianos, knife -> knives, lady -> ladies, suffix -> suffixes, foot -> feet.