A.was playing
B.had played C. played D. is playing
C.
D.

A.result in
B.hold on C. take over D. keep to
C.
D.

A.is he
B.does he C. isn't he D. doesn't he
C.
D.

A.knowledgeably
B.knowledgeable C. knowledge D. know
C.
D.

A.light-hearted
B.big-hearted C. warm-hearted D. whole-hearted
C.
D.

A.As soon as it stops raining
B.After it had stopped raining
C.When it stopped raining D. Once it stopped raining
D.

A.mood
B.luck C. fortune D. merit
C.
D.

A.Was built
B.Building C. To have built D. Built
C.
D.

A.destruction
B.assessment C. improvement D. pollution
C.
D.

A.harmful consequences
B.effective techniquesC. latest developments D. useful experiments
C.
D.