Not until the early years of the 19th century____ what heat is.
| A． man did know | B．man knew | C．didnot man know | D．did man know |
Sarah looked at ________ finished painting with ________ satisfaction.
| A．/；a | B．a；the | C．the；/ | D．the；a |
The parents were shocked by ________ news that their son needed ________ operation on his knee.
| A．a；/ | B．the; / | C．the; an | D．a; an |
People develop ________ preference for a particular style of learning at ________ early age and these preferences affect learning.
| A．a；an | B．a；/ | C．/；the | D．the；an |
Marco Polo is said to have sailed on ________ Pacific Ocean on his way to Java in ________ thirteenth century.
| A．the；a | B．a；/ | C．/； the | D．the；the |
It was________cold winter night and the moon was shining brightly across________night sky.
| A．/；a | B．a；the | C．the；a | D．the；/ |