This is Winglish, Mr.kim speaking!
这里是文各力士，敝姓金。
Who's caling,please?
您是哪位？
Who's this?
您是谁？
To whom do you want to talk?
帮您转接哪位？
Hold,please.
请稍等
Don't hang up.
请稍等
Just a moment,please!
请稍等
I'll get him for you.
我将为您转接。
I'll get him through.
我将为您转接。

如果对方要找的人不在，可以这么说
He just left.
他刚走开。
He stepped out for lunch.
他去吃午餐了。
He'll back in 1 hour.
他一小时后回来。
He's not in yet.
他还没来。
Try his cell phone.
给他打手机吧。

主动打电话时的用语
This is GE.Mr.Lee speaking.
这里是GE,敝姓李。
Is this Samsung Electronic?
是三星电子吗？