If you “visited a gallery,” I will know that you were at the gallery because the gallery was the place you visited. If you “emailed some friends,” then people will understand that your friends got the emails because that’s where the email went.

As the previous responder said, “to” simply indicates a direction. But if the direction is obvious in the context of the sentence, then it’s redundant to add the word, “to;” therefore, it’s usually not included in the sentence.

A transitive verb is a verb that requires both a subject and one or more objects. Like…

Jeff sees Donna.

I run laps.

She drank juice.

Verbs that don’t require an object are called intransitive. This includes verbs like sleep. You can’t sleep something, so it makes no sense.

VISIT is transitive. I visited a gallery.

Email is transitive. I emailed a letter.

Visit is transitive, which means it requires an object.

Here’s something to confuse you: In English, if something is the “object” of a verb, that is all it is. It can NOT be the object of a preposition. So you can not visit TO a gallery. To is a preposition, and gallery would be the object of a preposition. But it can’t be, because gallery is the object of visit.

THIS differs from other languages, which have their own peculiarities. For example, in FRENCH, such a verb might require a preposition “á” or “de.”

Idioms can be the craziest things. You just have to learn what needs what in what language.

This could get very confusing, especially if you are bilingual. Try reading this:

http://en.wikipedia.org/wiki/Transitive_verb

if written in the past tense, the action is already done so no ‘movement’ or ‘direction’ is necessary or taking place. ‘To’ also indicates something ongoing.

Follow this link for more info

http://www.m-w.com/cgi-bin/dictionary

all the best

so TO is already there. using it again would just be repeating it.