98.10

liul781

5. _____ no real boundary to the part of the ocean referred to as a "deep" because of changing water levels and movement in the sea floor.

(A)  It is

(B)  To be

(C)  Being

(D)  There is

answer:  D         why not A ?

37. Algae have been an extremely important link in the food chain after the beginning

                                          A                            B                                C

of life on Earth as we know it.

answer:       C         after-----------since

why not D   life------------the life

thanks a lot!!!!

思愔奶茶

5、若果选A, 那就是指代不明，It不知道指代什么？

37、具体的我也不太清楚，我就知道，过去时用Since