Sentence Diagramming: Flashcard 20

The modal auxiliary verbs may, might, can, could, should, and must are so closely tied to their complements (the verbs that complete them) that the two (modal auxiliary and complement) are considered single verb forms (may arrive, can help, should wait, must have seen, etc.) and are so diagrammed, as you already know. Other verbs achieve this same closeness with their complements (ought to hurry, am going to meet, used to watch, etc.). In such a construction, the infinitive that complements the introductory word, is usually preceded by the particle to and is called a complementary infinitive. Examples: "Students have to stay in their homerooms until the bell rings," "Students ought to stay in their homerooms until the bell rings," "Students are to stay in their homerooms until the bell rings," "Students are going to stay in their homerooms until the bell rings," "Students used to stay in their homerooms until the bell rang."

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Infinitives and infinitive phrases can function as predicate adjectives. The infinitives may be preceded by forms of the verb to be, but they can also follow other linking verbs, for example, seem, appear, and certain passive verbs. Here are some sentences that use infinitive phrases as predicate adjectives: "He seemed to have all his ducks in a row," "One contestant appears to lack self-confidence," "The Royal Library of Alexandria is thought to have contained more than 500,000 books," "This is said to be the best Vietnamese restaurant in town."

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In a peculiar construction, the particle for is used as an expletive to introduce an infinitive phrase used as (1) a subject, (2) a direct object, (3) a predicate nominative, or (4) an appositive. Such infinitive phrases have subjects. Examples: "For us to deny our common humanity would be harmful to society" (subject of infinitive: us), "The old man does not like for others to do his work for him" (subject of infinitive: others), "The plan was for him to read the script first" (subject of infinitive: him), "It is essential to the success of the company for all employees to contribute their time and talents." (subject of infinitive: employees).

An infinitive phrase can also be used as the object of the preposition for: "The salespeople were itching for the last customers to leave the store," "The boss bought a second car for the staff to use" (subjects of infinitives: customers and staff).

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Infinitives and infinitive phrases can be used as independent expressions, as they are in the following sentences: "To tell the truth, I’ve never caught a really big fish in my life," "Kay made a good impression, to say the least."

As you make your way through these flashcards, you may wish to refer to a section of my website that deals with terminology, www.german-latin-english.com/diagrammingterms.htm. 
On the right is a diagram of the sentence "To be sure, for the children to survive the famine, it is necessary for us to contribute generously." The sentence contains three infinitive phrases. The first, to be sure, is an independent phrase. The second, the children to survive the famine, functions as the object of the preposition for. The third infinitive phrase, for us to contribute generously, is in apposition with the subject of the sentence, it. Here, for  is not a preposition but an expletive; unlike a preposition, it does not indicate a relationship. In diagramming, independent expressions are not connected to the rest of the sentence; thus, to be sure sits unattached at the top of the diagram. The pedestal within the parentheses following it shows that everything on the pedestal functions as an appositive of it. The pedestal on the line reserved for the object of the preposition for shows that everything on the pedestal functions as the object of the preposition. The two vertical subject-predicate dividers preceding infinitive phrases indicate that the words to the left of the line (in this case, us and children) serve as the subjects of the infinitive phrases, which constitute the predicates. You might wish there were a way of diagramming the expletive for differently from the preposition for. I do have a suggestion: Why not put the expletive for on a broken diagonal line? Flashcard 21: more about participles.

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