21．Since then ,they have launched a great to make the beaches safer for swimmers and tourists.
A．campaign B．revolution C．competition D．organization
22．A suitable to the engine of his second-hand car was made to improve its working condition.
A．achievement B．admission C．assessment D．adjustment
23．David got promoted in three months, for his boss realized that he was a man of considerable .
A．confidence B．competence C．independence D．tolerance
