this is a testimony of a missionary to hong kong gand members and how she wanted more than "normal" goodies to power change lives through private prayer in tongues.
be encouraged to continue in your privacy to pray in tonguee

She opened a youth club. It met in a succession of shabby rooms, but the gangs, whose members were mostly teenagers, responded. She was soon deeply involved.

"When people were hurt in gang fights I took them to hospital, I visited them in prison," she recalls. "We went on picnics and barbecues and things, and they were very touched by my loving them and helping their friends—but not changed."

Despite this, she pressed on, pursuing what she calls "normal" gospel—
feeding the hungry, clothing the naked and caring for other basic needs. In spite of themselves, the gangs warmed to her commitment.

"They said about me, 'Oh, she's crazy about Jesus, but apart from that she's all right,'" Pullinger says. It encouraged her, but she adds: "I wanted to see them changed because I knew that some of them would die ... before they believed in Him."

Chasing the Dragon

One day she met a Chinese Christian couple who opened up a significant means of change. "They were just simple, uneducated people, and I thought, if they met a drug addict, instead of taking him to a clinic, they'd probably pray for him. And I hadn't met anyone who'd do that."

After a time of prayer with them, Pullinger started speaking in tongues, but says: "My life didn't change. ... I didn't feel good praying in tongues, so I didn't use it." It was another year before she met an American couple who she says told her: "The Scripture says if you pray in tongues you will be built up spiritually. It doesn't say you will feel built up."



So she began using the gift of tongues, and it opened a new door. "I would walk down the street, bump into a gangster—some of them I knew, some of them I didn't—and they all started to believe in Jesus, and I saw people healed. ... Because I was praying in the Holy Spirit, God was able to lead me to people He'd got ready.

"The problem is, most of us have got an agenda, and we say, 'This is what I want to do, dear Lord, please bless me.' ... But when you pray in tongues it's the opposite way round. It's, 'Dear Lord, You've got an agenda, and I'd like to play the part You want me to play in it.'"

Pullinger's book Chasing the Dragon tells how, slowly, through prayer and persistence, she won credibility with the gangs. "We've been watching you," one gang leader told her. "What we want to know is if you are concerned with us. Now you have been here for four years, and we have decided that maybe you mean what you say."

http://www.charismamag.com/site-archives/146-covers/cover-story/2491-one-woman-vs-the-dragon


and if you need more clarification i recommend this ebook - answers a lot of questions on speaking in tongues...https://drive.google.com/open?id=0BxrT0F-mwJf1NWdGelk3enMzZ2M