Frankly, I was amazed when she took to you so quickly but, retrospect, perhaps it's not so surprising after all.

A. at
B. in
C. out
D. up

The company went bankrupt and defaulted its initial payment of $40 million.

A. in
B. at
C. on
D. out

When a severe winter is setting, the poor people soon face food and fuel shortages because they have few resources to fall back on.

A. at
B. up
C. in
D. down

The tension between the two countries got increasingly worse, culminatinga declaration of war.

A. out
B. up
C. at
D. in

匹配介词填空。