我们。。。吧

[julio]

Among all the content I have studied in learning Chinese, is the pattern 我们。。。吧, that convey the idea of Let’s (do something). 
In the recent book I added to my collection, the sentence “Let’s ask the teacher” is translated as “让我们问老师”

This make me hesitate about the use of 我们。。。吧， and think that not always can be used. 
I would appreciate if someone can give me a little bit of clarity about the translation that I would have translated as “我们问老师吧”. 
thanks

[7800]

Don't focus on "我们。。。吧", 吧 alone is doing all the work here, it's all about 吧. We use 吧 to make a suggestion, and for some other things, but learn those some other time or it gets confusing. You've kind of already decided to do something, or you're telling someone to do something , but you don't want to sound forceful, so you add 吧 at the end of the sentence. 

You want to go ask the teacher, and you're suggesting to go as group and ask the question: 我们问老师吧, or even 我们去问问老师吧。
You want to tell someone to go ask the teacher: 你问老师吧。

You're suggesting to meet with someone at a 5 o'clock: 我们5点见面吧。

 

You can use 让 to express a call to action, "let's do this". I feel like it sounds much more serious than just using 吧. It ends up conveying the same meaning as 吧 sometimes, but they're not the same thing. In all languages there are many ways of saying the same thing, your translation won't match other's most of the time, don't worry.

[Babylon]

In real life nobody would say 让我们... due to it's not polite for the imperative mood, and sounds kinda weird. that's obviously a direct translation from English ...

 

[julio]

Thank you, a lot Babylon, 7800.

[Babylon]

On the other hand the "让" usually equals to the "permit" or "allow", so we can beg this to the boss, 请让我们下班吧 我们不想加班了 Please permit us to get off work, we don't wanna work overtime anymore. Not the boss willing to let us to do that, the boss would only say let them keep working 让他们接着干活!

[julio]

Thank you very much for your detailed explanation. I will look for diferent examples. Thanks. 

[Babylon]

I have to mention a song <让我们荡起双桨> <Let's paddle our oars>, you know, 90% Chinese people are familiar with this song, because it's a passage inside the third grade elementary school textbooks. In this case the "让" expresses a wish, an imagination, since we all can't do that right now while we are listening or reading that lyric in a room. So we usually use "让" like "让我们飞向月球吧" "让我们形影不离" ... to assume an impossible hypothesis.

[leonjust]

actually we don't say "让我们……吧"in our life，we just say "我们……吧"

“让我们……吧”is very very polite, it only can be seen in primary school's book,and even primary student don't even say that.

so just forget the"让"