When a journalism professor gave students the sentence “He snapped to attention only when a tourist asked directions,” a number of them added “for” after “asked.” The prof wrote, “They swore they’ve never seen that phrasing.”
“That phrasing” is yet another example of how some verbs that can be transitive or intransitive often change their objectives.
An “intransitive” verb, of course, is one that acts on its own, without an object. “You lie!” doesn’t require that you know the object of the untruth. A “transitive” verb needs something to act upon: “Do you like blueberries?” needs “blueberries” to complete the liking.
Prepositions often make an intransitive verb move to the other side. “Ask” is definitely one of those. When you “ask a question,” you’re using the transitive; when you “ask for directions,” you’re using the intransitive. Yet you hardly have to move at all to get from “a question” to “for directions,” so “ask directions” is born. (People also ask for “some directions,” which sounds better to many ears than just “ask directions,” and better justifies the transitive.)
Other prepositions that cause the transition include “from” and “on.” Many a journalism graduate was taught (in the hot-type days) that a student “graduates from” college; nowadays, more students just “graduate college.” We’ve already discussed how “wait on tables” has become plain “wait tables,” and children have become mere objects in the morphing of “baby-sit for the kids” into “baby-sit the kids.”
Strictly speaking, those transitional transitives are not incorrect, merely grammatically flawed. If you pride yourself on your adherence to “proper” English, by all means re-insert the prepositions and move the verbs back to transitive. If you’re blogging, or trying to be more colloquial (read: hip), go ahead and jump. Just be prepared for some of your readers to jump (on) you.