You can only be sure of _____ you have at present; you cannot be sure of something _____ you might get in the future.
A. that; what B. what; / C. which; that D. /; that
The traditional view is _____ we sleep because our brain is “programmed” to make us do so.
A. when B. why C. whether D. that
We arranged to meet at the cinema at 7:30, but he failed to ______.
A. turn up B. turn on C. turn out D. turn over
Miss Green contributed fifty dollars, but she wished she could contribute _____.
A. one other fifty dollars B. the same amount also
C. more fifty dollars D. another fifty
When _____ different cultures, we often pay attention only to the differences without noticing the similarities.
A. compared B. being compared C. comparing D. having compared
Hundreds of species are declared to _____ in the coming century.
A. die away B. die out C. die down D. die off
