pls check it for me

[greenhand]

=================
Ellen: OK, Philip. This is your third cup of coffee. We should get to work, or we won't be finished by dinnertime.
Philip: I guess we must.
Ellen: We must.
.....
=================

My friend was wondering if there is anything wrong on the fowllowing saying "OK, Philip. This is your third cup of coffee. We should get to work, or we won't be finished by dinnertime. "

i think it's ok..pls check it for me

thanks :)

[Francois]

Looks fine.

FRC

[Tdol]

I'd say 'get down to work'.

[Francois]

Yes, sounds even better. Is 'get to work' correct though?

FRC

[Tdol]

It's OK- it could either mean 'go' or 'start', but 'get down to' is more natural.

[Francois]

Obviously.
TY!

FRC

[greenhand]

my friend's question are:

1. why say"we won't be finished" but not "won't finish"

2. why use "by dinnertime" but not "before dinner time"?