If each gene in the human genome __________ thoroughly understood, many human diseases could be cured or prevented.

A. can pick

B. needn't pick

C. should be picking

D. can be picked

A. variety

B. influential

C. associate

D. accountancy

A. The more carefully I prepare for the lesson, the more confident I am in class.

B. The more and more confident in class I am, the more and more carefully I prepare for the lesson.

C. The more confident I am in class, the more carefully the lesson I prepare.

D. The more carefully I am, the more confident the lesson is.

A. harmful effects of pesticides

B. endangered species

C. survival of peregrine falcon

D. releases into the wild

A. enter

B. come

C. arrive

D. go

A. include

B. account

C. accelerate

D. respect

A. When having dinner

B. When I am having dinner

C. While I was having dinner

D. While having dinner