I'm not sure which tag question to use after a sentence that begins
with Let's. I have always used shall we, as in:
Let's go, shall we?
But the black Azar says that okay? is used more informally.
How can we know when to use the informal alternative?
Shall we is a perfectly correct tag ending with the
It is more formal in tone than its alternative okay?
It's also somewhat more authoritative. Here are examples.
At a formal business meeting:
(a) Let's start now, shall we?
(b) Let's start now, okay?
Both are fine, but the speaker is making more of a declaration in sentence
(a), and is asking for consensus in sentence (b).
Here's another example:
Two friends riding in a car together:
(c) Let's stop at the next rest area, shall we?
(d) Let's stop at the next rest area, okay?
In this situation, sentence (c) might be too authoritative;
sentence (d), with okay, is appropriate for two friends,
one asking for agreement from the other.
One reason for using any tag ending is that the speaker hopes to elicit
confirmation of his/her idea from the listener. Both shall we
and okay? accomplish this.
In American English, however, the shall we tag is
not very common, although it has a certain formal charm. In addition
to using okay? we can make an alternative kind of first
person plural imperative in other ways, as in these sentence types used
for requests or suggestions:
Why don't we stop at the next rest area?
Could we stop at the next rest area?
I'd like to stop at the next rest area.
How about stopping at the next rest area?
Wanna stop at the next rest area?