A vinaigrette is a thin, sharp-tasting salad dressing made by mixing oil with vinegar and adding salt and pepper. Cooks usually use about three parts oil to one part vinegar, and often add mustard, garlic, honey, or herbs. Because oil and vinegar do not stay mixed, you shake it in a jar or beat it hard just before serving, and it separates again after a few minutes — that is normal, not a mistake. The key contrast for a learner: a vinaigrette is thin and clear-ish and sour, while dressings like ranch or Thousand Island are thick, creamy, and white, because they are built on mayonnaise or cream. In Taiwan, the bottled dressing many people picture first is the creamy or the sesame kind (和風醬 is closer in spirit — thin, sour, oil-and-vinegar based — though it is soy-flavoured and Japanese in style). It is a countable noun, so you can say a vinaigrette or three different vinaigrettes, meaning three different versions of the recipe. It also works as an adjective in menu language: "asparagus vinaigrette". The word is French, and English kept the French spelling and roughly the French sound, so it looks harder than it is — say it vin-uh-GRET, and note that the g is silent.