Coherence and Cohesion: Contrasting words and phrases

Which words are used to introduce contrast clauses?

She would like to get married. However, no man is good enough for her. 

Few people knew about the club; however, Lawrence did. 

They have spoken to Candace. James, however, was not there. 

I, for one, wanted to try. However she didn't. 

Which prepositions are most often used after "in contrast"?

What is the difference between a contrast clause (e.g. While I like pasta,) and a concessive clause (e.g. Although I like pasta,)? 

Concessive clauses provide information about a cause, not a contrast

Concessive clauses provide unexpected or surprising information

Concessive clauses are the same as contrast clauses

Concessive clauses provide information about a result 

In spoken English, what's the most common word used to contrast two or more pieces of information?