What can you say about a 7-year-old gorilla who lies? That she likes rhyming and the color red? That she laughs to herself and talks to her dolls? That she takes bribes?

Koko, who lives at Stanford University in Palo Alto, Calif., and uses sign language to make herself understood, does all of these things, and while there is something distressing about discovering that the denizens of the animal kingdom might not be quite the paragons of virtue that one had been led to believe, Koko's teacher, Francine "Penny" Patterson, hangs on her every word.

Patterson has spent the last six years working with Koko, teaching and testing her and recording her behavior, and she plans to spend the rest of her life along the same lines. She hopes Koko and her male gorilla friend, Michael, settle down and form a nice, respectable nuclear family.

This part of her future is not advancing at quite the pace that Koko would like, since Michael hasn't yet begun the trials of adolescene and hasn't a clue to what Koko is talking about when she asks him to "walk up her bottom." Otherwise, life is proceeding quite pleasantly in Koko's modest mobile home at Stanford.

At this point, with a vocabulary of about 375 signs, Koko has learned about extortion (refusing to answer questions or to continue with a lesson unless given an edible bribe), secrecy (she will sometimes sit and laugh up-roariously at something in a magazine until one of her teachers appears on the scene, at which point she'll slam the book shut) and betrayal (asked once who had broken something in her classroom. Koko said, "Michael").

All of which should be of enormous help to her in getting along with the human world, although, to her credit, she apparently spends much more of her time being amiable and cooperative - especially when you compare her to most adolescent girls.

She has even been gracious enough on occasion to give advice to Jane Goodall, the famed anthropologist who is busy studying chimpanzees in the wild. Goodall, Patterson said yesterday at the National Geographic, has asked Koko whether the chimpanzees would prefer being studied from a standing position or a seated one (koko's advice: the lower the better) and how much she can tell about a person from taste and scent. That one still seems open to question.

When not working as a consultant, Koko usually meets up with Patterson at about 8 a.m. and has the usual day expected of a young student gorilla - cereal for breakfast, a little light housekeeping to get the mobile home in order, English lessons and regular sessions with the videotape recorder, followed by a little lunch and a walk and a drive in the country. In the afternoons, while Patterson leaves to do other research or to write, Koko has Michael to play with, talk to, berate, or, so far without success, to seduce.

Koko, who is a vegetarian for the most part though a little hamburger is included in her diet, dines at 5, and is in bed by 7:30, leaving Patterson free for the evening but on standby should anything go wrong.

Life in the mobile home is gracious, if increasingly crowded, but Koko's life and times have not always been so tranquil. Patterson began working with Koko in 1972, when Koko was a year old and an inmate of the San Francisco Zoo, where she was recovering from malnutrition.

Until last year, Koko, remained the property of the zoo which, Patterson said, did not always turn a sympathetic ear to the priorities of scientific research and instead wanted Koko back for breeding purposes (gorillas being a rather rare and expensive zoological item).

Last year Patterson set up the Gorilla Foundation, which now officially owns Koko and which bought her from the zoo for about $12,000.

Despite the traumas of her early childhood, Koko maintains a rip-roaring sense of humor, although her teachers don't always get her jokes. "I asked her once to tell me what she thought was funny." Patterson said. "And she answered by asking me what I thought was funny. And it was terrible - I just couldn't come up with an answer."

Sometimes, when Koko is bored with answering questions like "What kind of an animal does not live in water," which tests her grammar or with identifying the same picture in a picture book, which tries her patience, she will answer her questioners in rhymes.

"Squash," says the teacher.

"Wash," says Koko, which is doubly difficult for her, Patterson explained, because she is in effect translating into a different language - hearing the rhymes in spoken English and articulating them in American sign language, the method of communication used by about 200,000 deaf people in this country.

In the manner of most teen-agers, the gorilla does not speak only when spoken to, behavior which, because she is a gorilla and not a Sean Cassidy fan, is encouraged. Koko has been observed talking to her dolls, telling them which one has been good that day and which has been bad.

This rather Calvinist preoccupation with guilt and innocence is continued as well in her solitary pursuits. "Bad," she will tell herself angrily, while nevertheless sitting in a corner ripping to shreds some material she was not supposed to have, "Koko bad."

And while there is something of a generation gap developing between Patterson and Koko - "she's at that stage, said Patterson, "where she thinks she doesn't need anyone to tell her what to do" - at least there's no current identity crisis.

One day, Patterson said, she was sitting with a colleague who referred to Koko as an adolescent while Patterson was calling her a juvenile. No, Koko informed them, she is, in fact, a gorilla.

She is also something of a photographer. The current issue of National Geographic, which supports Patterson's research with about $25,000 a year, has a self-portrait of Koko on the cover, for which she was paid the standard $750 cover picture fee, according to a Geographic official.

Koko has the vocabulary and learning skills of a child about three or four years behind her, and her IQ has been tested at about 85. Unfortunately, Koko is the victim of something of a cultural bias in such tests. For instance, when she is asked where she would run for shelter, and the choices are a hat, a spoon, a tree and a house, and she picks a tree, she is marked wrong, despite the fact that gorillas feel more secure in trees.

Patterson, who is pleased that this research is finally being taken seriously enough that she doesn't have to listen to too many jokes about blond women and great apes, is crazy about Koko. "She surprises me every day," she said. "It's clear that she possesses most of our capacities in at least rudimentary form. I think Darwin would have been very pleased."

And while there are lots of good reasons and unquestionable benefits to teaching a gorilla to communicate - the clues it gives on the transfer of culture and the evolution of intelligence, for instance, or techniques it may help to develop that could be used to teach disturbed and retarded children - there is one even more fundamental reason why Penny Patterson thinks Koko is worth just about every minute of her time.

"Gorillas," she says, "are just a whole lot more fascinating than people."