Article in English: You should add a dollop of mustard that is about the size of your fingertip. Mustard acts as an emulsifying agent--when two liquids don’t mix, like water and oil, mustard breaks them down and helps them to mix. You can also add a fingertip-sized dollop of mayonnaise to the bowl. Mayo is also an emulsifier and adds a nice creamy texture to the vinaigrette. However, for a lower-calorie vinaigrette, skip the mayo. This item will depend on the kind of vinaigrette you are making. The most standard vinaigrette is one made with lemons. Squeeze one fresh lemon into your bowl. If you don’t have a fresh lemon, you can also use four tablespoons of bottled lemon juice. Whisk the lemon juice with the other ingredients in the bowl. Make sure that it is thoroughly mixed. Other options for your acidic element include red wine, white wine, and apple cider vinegar. To properly combine all of the ingredients, continue to whisk the lemon mixture while slowly pouring in the olive oil. Whisking while pouring will help the water-based lemon juice combine with the oil. Continue to whisk until all of the ingredients are thoroughly combined. For a basic vinaigrette, all you need to ad is salt and pepper. Add as much or as little as you like. Season to taste. If you want to add other herbs, now is the time to do so. Other herbs you might like to add include:  Minced garlic, onion, or shallot. Finely chopped basil, parsley, thyme, or dill. Other spices like paprika or cumin. Only do this right before you are about to eat so that the lettuce does not get soggy. Enjoy!

Summary in Chinese:
在碗中挤少许芥末。 在碗中加入酸味剂。 加橄榄油。 加调味料。 把油醋汁倒到沙拉上。