Theory:

 
No.
Words
Meanings
1
complexesconsisting of many different and connected parts
2
demandedask authoritatively
3
establishset up on a firm and permanent basis 
4
decidedhaving a clear opinion
5
boardedget on or into a vehicle
6
outskirtsthe outer parts of a city/village etc.
7
consoledcomfort someone at a time of grief
8
exchangedgive something and receive something
9
quarrela heated argument or disagreement
10
healthy competitionproductive improvement for all competitors
11
affectedcause a change to someone or something
12
astoundedshocked or greatly surprised
13
hesitatinglyto be reluctant, wait before doing something
14
rosepast tense of rise - come up or move up
15
dumbfoundedspeechless with amazement