To 'touch' means to connect physically or emotionally with someone or something. If you are ‘in touch’ with somebody, it means you are in communication with or connected with that person in some way: “Have you been in touch with the client recently? -Yes, I called him yesterday.” To be ‘in touch with’ is a common expression you will hear in social and professional contexts. Similar expressions include ‘keep in contact with’ or ‘touch base with.’

If you are ‘out of touch’, however, it means you don’t know about something or have no knowledge about it: “I am out of touch when it comes to computers and the internet - I don’t know anything about them.” Being ‘out of touch’ has the implication that you are liable to make mistakes. This is an expression especially used to talk about older people or those disconnected from a particular trend or part of life.

1. It was great to see you. Make sure you keep in touch.
2. It's important to keep in touch with your friends. I fell out of touch with my friends years ago!
3. I've been in touch with your teacher. He said you did well in your test.

1. I need you to get in touch with all of your clients. I want all of them to know about our new service.