Hi Kevin. The first sentence implies there are other ingredients too, which you aren’t mentioning. The second sentence implies the salad consists of only those three ingredients you mention.

Neither statement conveys unambiguously that the salad has only those three ingredients. For that: The salad contains only … Or more colloquially The salad is … Without context, ‘includes’ is rather formal but vague. I would only use it in a context where the importance of those ingredients being in the salad has already been established. Otherwise you can just say The salad has …

I would rather use the word "includes" if I'm telling somebody the recipe of my salad or the importance of consuming these ingredients in a salad. Otherwise "has" is more commonly used. The salad has lettuce, tomatoes, and whatever the ingredients are.

Both sentences are correct and mean the same thing. However, "includes" is more commonly used in everyday language. Sentences: 1. "The salad includes lettuce, tomatoes, and cucumbers." 2. "The salad contains lettuce, tomatoes, and cucumbers." Common Usage: * "Includes" is more common.