A.Were
B.Had
C.Should
D.Unless

A.The reasons why many people like tuna
B.Causes of the low population of tuna.
C.Various types of tuna
D.Declining tuna stocks and our actions

A.dangerous
B.serious
C.poor
D.favorable

A.to go upstairs to bed
B.to revise lessons
C.to change his mind
D.to reduce the rate of study

A.to go upstairs to bed
B.to revise lessons
C.to change his mind
D.to reduce the rate of study

A.obey
B.memorize
C.review
D.compose

A.attendants
B.representatives
C.participants
D.audiences

A.attendants
B.representatives
C.participants
D.audiences

A.People think that his family is rich, so he was born.
B.He is thought to be born into a rich family.
C.That he was born into a rich family is thought about.
D.He is thought to have been born into a rich family.

A.He reminded me to call him as soon as he arrived at the airport.
B.He denied calling me as soon as he arrived at the airport.
C.He promised to call me as soon as he arrived at the airport.
D.He objected to calling me as soon as he arrived at the airport.