Grammar sos!

<p>IS:
1. Just as the acrobats in the first ring began their (backflips, that was when) the trained dogs in the second rng began series of pirouettes, and the circus audience hardly knew where to look.
- backflips
Does "just as " act as a conj. here?
I have known that "just as...so..." What's the differences?
2.Under the new regulations governing tobacco advertising, the well-known ad (that shows people riding horses smoking cigarettes) will no longer be allowed.
- that shows people (smoking cigarettes while riding horses)
Could I understand it this way?
"while" here functions as "and". Just in Grammar. Nothing about actual meaning.
While functions as a conj. In grammar, smoking while riding is like smoking and riding?
The clause is "that shows people". "that" refers to ad?
Is it right?
ISE
1. In May, construction began on a second building that (will be attaching) to the existing one.
How to modify?
2. Between AD 350 and 550, Kolomoki, (in what) is now Geoprgia, was one of...
Why is it right?
3. Marisa became fluent in French only after she had lived in France for a while; she would not have acquired the language (as quickly) by studying French at home.
The answer is E.
I think that as + clause.
So cannot understand.
IP:
Even the phrase "household (words" that might partly entitle this essay) comes from Shakespeare's Henry V.
A. words." that could title, partly, this essay
B. words." part of a good title for this essay, maybe,
C. words." that would partly b a good tite for this essay
D. words." which some have suggested to be a good part of the title for this essay,
E. words." which could b part o a good title for this essay,
why chose E?</p>

<p>Thanks!</p>

<p>For the second improving sentences one, the phrase “that shows people riding horses smoking cigarettes” is wrong because one would get the impression that the horses are the ones doing the smoking.</p>