A:One of my old friends popped up in front of me yesterday.You cannot imagine how surprise I was at that time.

我的一个老朋友昨天突然出现在我面前。你想象不到我那个时候有多吃惊。

B:He must have your address.

他一定有你的地址。

A:But we have been out of touch with each other since we left school.

但是自从离开学校，我们一直没有联系。

B:He could get it from other friends.

他可以从你的其他朋友那里得到你的地址啊。

pop up

突然出现

She was startled when Lisa popped up at the  door.

丽萨突然出现在门口，吓了她一跳。

in front of

在...的面前；在...的前面

She stood in front of a tree.

她站在一颗树的前面。

She blamed me in front of everyone.

她在所有人没面前责备我。

out of touch

没有联系

We've been out of touch for years.

我们已经几年没有联系了。

To be frank with you,I have been out of touch with most of my old friends.

实话告诉你，我和大部分老朋友都失去了联系。