【单选题】According to the passage, Americans tend to ignore the rest of the world because ______.
A.
they are too proud of themselves
B.
they are not interested in other countries
C.
they are too busy to learn about other countries
D.
their country does not have many neighboring nations
【单选题】According to the passage, Americans tend to ignore the rest of the world because______.
A.
they are not interested in other countries
B.
they are too proud of themselves
C.
their country does not have many neighboring nations
D.
they are too busy to learn about other countries
【单选题】Ti质粒介导基因转移,转入植物细胞中的序列是( )。
【单选题】Why Americans travel overseas less than their western counterparts?
A.
Their vacations tend to be shorter.
B.
They can't afford international tours.
C.
They are more interested in making money.
D.
They prefer staying where Americans are in the majority.
【单选题】Ti质粒介导基因转移,转入植物细胞中的序列是( )