Polar bears live_______ on sea ice，which they use as a platform for hunting seals

The volcano eruptions are found ________around the Pacific ocean.

—Jenny,they say you have asked for a leave because of a sudden headache.I’m worried about you,and are you ________better now?—I’m all right now,thanks for your care.

—I heard Charlotte had been drowned in the lake.—Really！Her boat turned______,and ______she couldn’t swim.

—How______do you attend the evening classes?—______,three times per week.

As you study a globe,you may notice that ______ of the large land and areas are connected,or ______so.

The houses in this village are______built of bricks.

“John” and“Tom” are _______ names in the English-speaking countries.

—Since you like the fur coat so much， why not buy it?—Well， I can’t afford ______ coat. 

Tony can’t have received the invitation. ________, he would have attended your birthday party yesterday.

He has called several times this morning. _______, there is something very urgent.

The little man was _____more than one meter fifty tall.

This pair of trousers isn’t good but that pair is ____better.

It doesn’t make any difference how we get there because we’re going to be late________.

—Do you think our teacher is　　　　？—Yes， he always corrects our homework and prepares his lessons　　　　. 

The committee is discussing the problem right now. It will ______ have been solved by the end of next week.

---- How is everything going on with you in Europe? ----Quite well. Not so smoothly as I hoped, _________.

 _______ eager to get access to the president, the boy in northern America wrote a letter to him.

If there are natural resources      in a country, it is common for it to export some of them.

Under criminal law, people who      carry and use large numbers of fake banknotes will be sentenced to less than three years in prison.