5  Even ______ seem insignificant remains can shed interesting…(11. 8-9)

a．they

b．which

c．what

d．those to

6  Historians are now able to read this difficult code ______ markings made in… (11. 15-16)

a．with correlating

b．having correlated

c．which correlates

d．for they correlate

7  ______ be a definite relation between these paintings and the…(11. 19-21)

a．It could

b．There can

c．There may

d．It might

Vocabulary词汇

8  Historians have long tried to ______ dots, lines and… (1. 13)

a．puzzle

b．puzzle out

c．riddle

d．detect

9  By correlating markings made in ______ parts of the world…(11. 15-16)

a．different

b．several

c．many

d．other

10  ---- historians have been able to read ______ . (1. 16)

a．these puzzling signs

b．this hard law

c．these difficult signals

d．this uneasy letter

11  Until recently historians assumed that calendars ______ with the advent of agriculture. (1. 10)

a．came to existence

b．came to existing

c．came to exist

d．were existential

12  The people who lived by hunting and fishing during the last Ice Age ______ . (11. 14-15)

a．wandered from place to place

b．lived in villages

c．first learnt to write

d．learnt how to farm the land