[单项选择]The symbols of mathematics ______we are most familiar are the signs of addition, subtraction, multiplication, division and equality.
A. to which
B. which
C. with which
D. in which

[单项选择]The symbols of mathematics ______we are most familiar are the signs of addition, subtraction, multiplication, division and equality.
A. to which
B. which
C. with which
D. in which

[单项选择]The symbols of mathematics（）we are not familiar are the signs of addition, subtraction, multiplication, division and equality.
A. to which
B. with which
C. which with
D. in which

[填空题]The author was most probably a tenant of the family.

[单项选择]

We first think of the traditional or nuclear family. This is a two-generation family, the father and the mother and their own children. Most couples wanted to have four children, two boys, two girls.
Some nuclear families, however, may add one or more grandparents to come to live with them, that is three generations. This kind of family with grandparents, parents, and grandchildren is called an extended family. This family type was not very common during the later half of the twentieth century, but it’s becoming more common now as an elderly grandparent moves in to live with a son or daughter. This is more possible now that American homes have become larger. What is interesting, however, is that after the grandchildren move out of the home and start their own families, this extended family shrinks back to a nuclear family, with just two generations again living together, a grandparent and parents, with the grandchildren coming only for occasional visits.
Now
A. The children’s aunt.
B. The children’s nursery or school.
C. The children’s grandmother.
D. The children’s neighbour.

[单项选择]One of the most vivid symbols of global warming is the torrents of melt water that drain from the lakes that form each summer on Greenland’s ice sheet.
Recent studies have shown that this water, which flows deep into the ice through natural drainpipes called moulins, allows the ice to slide faster over bedrock toward the ocean. And the faster the ice flows, the faster sea levels rise. But a Dutch study using 17 years of satellite measurements in western Greenland suggests that the movement associated with the meltwater is not as rapid as had been feared. The acceleration appears to be a transient summer phenomenon, the researchers said, with the yearly movement actually dropping slightly in some places.
"The positive-feedback ,mechanism between melt rate and ice velocity," says the report, published Friday in the journal Science, "appears to be a seasonal process that may have only a limited effect on the response of the ice sheet to climate warming over the next decades.
A. the ice sheet responds to climate warming in a certain season
B. melt rate and ice velocity are mutually influencing
C. climate warming exerts only seasonal influence on ice movement
D. ice movement associated with seasonal melting is exaggerated