We've touched upon the topic of transitive verbs at fandom_grammar in "lie" versus "lay" and "rise" versus "raise", and in the feature on passive voice. Here is a more thorough discussion of transitive verbs in general.
Transitive verbs are action verbs that have a direct object—the verb acts on some "thing."
Sam rebuilt the generator."Sam" is the subject of the sentence, "rebuilt" is the action she took—the verb—and "the generator" is the direct object—what she took action on.
Sounds easy, right? It should be a snap to pick out the transitive verbs from these Stargate SG-1 examples:
1. "Remember, I am the doctor; you are the patient." At Fraiser's warning, Jack sat abruptly.
2. "We are going home. Dial the gate."
3. Daniel gave Sam the artifact.
4. The SGC scientists voted Col. Dixon "Most Likely to Blast Artifacts."
5. Sam traded Teal'c her pie for his blue Jell-o.
1a. The verb "to be," like all linking verbs, is not an action verb, so in Fraiser's warning there are no transitive verbs. "Doctor" and "patient" are equivalent to the subjects "I" and "you," and are not direct objects. Jack can become a model patient, Janet can remain a little Napoleon, and there will be no direct objects involved. For more, see the section on linking verbs in Grammar 101: Verbs.
1b. "To sit" is an action verb, but it doesn't take a direct object. Jack didn't sit something; he just sat. Most of the verbs for an action you take autonomously are intransitive (that is, not transitive): sleep, stand, fall, die—plus lie and rise, as we've seen before. Others can be intransitive or transitive:
Hearing the Jaffa, Sam ran.
After all that off-world conditioning, Sam ran the marathon easily.
2a. While "to go" is an action verb and "home" is often a noun, in this case "home" is not a thing that the team is acting the "going" upon. Here, "home" is being used as an adverb to describe where. If what comes after a verb doesn't answer who or what, but answers where, when, or how, it's an adverb or adverb phrase, and is not a direct object.
2b. "Dial the gate" is a classic example of a transitive verb and direct object. "To dial" is an action verb, and "the gate" is what is acted upon.
3. Transitive verbs must have a direct object, although sometimes there is an indirect object, too. (Verbs of giving, telling, and showing often include an indirect object, which indicates the person to whom the direct object is being given, told, or shown.) Here, the thing Daniel "gave" was the artifact—the direct object—but you have to include the indirect object "Sam" for the sentence to make sense.
4. In this case, the action verb "to vote" has two direct objects: the voting was acted upon a recipient and the voting was acted upon a title.
Whenever a transitive verb acts upon two objects, whether it's a direct and an indirect object, as in 3, or two direct objects, as in 4, it can be called a ditransitive verb. (You don't really need to know this, but if you ever wanted to pull out a multisyllabic word, this is an impressive one.)
5. "To trade" is a rare tritransitive verb: "Teal'c" is the indirect object, and "pie" and "blue Jell-o" are two separate objects acted upon. (There's a ridiculously obscure grammar geekery for you!)
Another way to test for transitive verbs is to try to rewrite the sentence in passive voice. As discussed in the feature linked above, passive voice switches the direct object to the subject, so if there is no direct object, the sentence won't work. Let's try our examples:
Intransitive verbsTrying to make passive voice sentences from sentences with linking verbs or intransitive verbs just makes nonsense.
1a. "Remember, the doctor is being by me; the patient is being by you."
1b. At Fraiser's warning, ___ was abruptly sat by Jack.
2a. "Home is being gone by us."
Transitive verbsSentences with transitive verbs and direct objects can sometimes make for odd or convoluted sentences when switched to passive voice, but logically they work.
2b. "The gate is dialed by you."
3. The artifact was given by Daniel to Sam.
4. Col. Dixon was voted by the SGC scientists as "Most Likely to Blast Artifacts."
5. Sam's pie was traded by her to Teal'c for his blue Jell-o.
Many dictionaries will let you know whether a verb is transitive with a notation like [trans.], or vt, or (used with object), while intransitive verbs would be marked [intrans.], vi, or (used without object). As with "run," above, many verbs can be both transitive and intransitive in different cases. The dictionary entry will usually include examples of the verb in its different aspects for clarification.