They aren't 100% fluent and they need help with learning it. But they're NOT beginners! Maybe I could have conversations with them, and show them how to understand complex sentences?? What do you think? THANKS!

I'm fluent in English by the way.

television also helps people learn english...i know this because almost everyone i know that english is their second language that is new to the country has learned english from watching tv.

Practice.....I recommend they travel to an English speaking country, if possible. That would be total immersion.

If they can't do that, have then go to an area where many foriegners hang out. For example, Roppongi is famous in Tokyo for being an area where foriegners hang out. I recommend practice. Practice as much as possible.

japanese dictionary.

A decade ago to learn English, you had to attend costly English classes or purchase course material like tapes and books. Now you can learn English for free from the comfort of your home using the Internet. The BBC and the British Council offer a number of on line courses, which teach written and spoken English. You can also improve your English by watching television programs and reading English newspapers. For more information, visit http://tinyurl.com/qnzpt

I am a Japanese living in North America for over a decade.

I think the most easiest way to learn is submerging them self in the language and culture. Listen and recognize the English words and sentences, and talk the ways you just learned and do the same thing over and over for a very long period of time. Also they have to read books in English, watch movies and sitcom in English and study grammar... I think talking with them should be a definite help, however it demands the proper teaching skills and patience before you see the improvement.... I taught Japanese to American.....

Your second language will never be perfect. It is absolutely normal and that's the way it is... Also your facial muscle is developed for speaking your first language. It is very hard for adults to adapt new ways of movement. If you are a underage and able to pick up language faster than adults, then it may be possible.

i helped a korean girl learn english and the best way is to talk and explain and to work and work at it for a long time, have them talk as much english as they can, if they are wrong itll be fine and the more practice the better. also there is a really good computer program for that but it is like in the hundreds of dollars.

conversations, lost of them. Try to avoid using slang and talking to fast. But do not speak to slow or childish, it will take a few adjustments.

Another thing you could do is ask them to keep a short English journal. Write a few sentences each day and when you meet, you can read over it w them and write some suggestions. That will give them something tangible to refer to when they forget what they want to say.
Also you can try to tie in their hobbies or interests to language study. For example, if they like karaoke they can learn some English songs. Or if they like cooking they can read an English cookbook and try to follow a recipe, etc.

Like the other person said- talk to them as much as possible in English, but slowly. Try not to use too many hard words, but it would be a good idea to introduce a couple every now and then, so they feel that they're learning something. Stick to basic conversation topics and stay away from difficult subjects like politics or science.