Researchers in Germany and France are trying to solve the problem of traffic jams by analyzing drivers' behavior. According to their model of traffic flow, if everyone drove consistently, we (A /B/C) to our destination more quickly. A WOULD HAVE GOT B WOULD GET C WILL GET B- would get- is correct Traffic can be in one of three states: free flowing, synchronized or jammed. Synchronized flow (A / B) on busy motorways, but until now no one has known how cars synchronize. A IS OFTEN OBSERVED , B OFTEN OBSERVED A - is often observed- is correct AROUND APPROXIMATELY ROUGH DIFFERENCE around and approximately can be used more or else interchangeably when estimating a number for example- The population of Ireland is around 5 million/ approximately 5 million- around is less formal, approximately is more formal, used more often in writing and in academic writing/newspapers etc. Around is used more often in informal speech. Rough can also mean approximately, but it's an adjective, not an adverb. It can also mean something unpolished/possibly unfinished or to describe a first idea or first draft. Example - This is a rough sketch of what the painting will look like when it's finished. I don't know what the final cost of the project will be, but here's a rough estimate.