Wash the tomatoes, then cut into small pieces and set in a colander to drain. In a large saucepan containing 7 pints(6L) of salted water, cook the pasta al dente. Drain the spaghetti in a colander Put the tomatoes, basil, garlic, parsley and a little oil into a large serving bowl. Add the hot pasta and mix gently to blend all the ingredients thoroughly. Add more oil, salt, plenty of pepper and stir gently again. Serve at room temperature.