There have been many（）in their marriage but they still love each other.

单项选择题The local government tried its best to ensure each of its citizens a（）supply of food at regular intervals (时间间隔).

A.consistent
B.continual
C.continuous
D.numerous

单项选择题The United Nations Conference on Global Environment, which took place earlier this year in Vienna, was a very（） meeting.

A.productive
B.communicative
C.aggressive
D.protective

单项选择题We watched the plane（）behind the clouds.

A.disappearing
B.disappeared
C.diving
D.dived

单项选择题Pipes made of plastic are now widely used in building as they are light and do not become （）in water.

A.ripe
B.instant
C.rotten
D.mature

单项选择题They were under the（）that the company was doing well, but in fact it was in serious trouble.

A.conclusion
B.expression
C.enjoyment
D.illusion

单项选择题This lovely old town has a（）you couldn't find in a big city.

A.condition
B.standard
C.situation
D.charm

单项选择题The starter (赛跑发令员) gave the（） for the race to begin.

A.advice
B.signal
C.glow
D.attention

单项选择题The football match had to be（）owing to (由于) the bad weather.

A.cancelled
B.advanced
C.arranged
D.held

单项选择题Jessica（）her father on the knee and asked him not to worry about his health.

A.patted
B.struck
C.stroked
D.paced

单项选择题Having（）the bear in the woods for one week, the man was almost out of food.

A.caught
B.shot
C.trailed
D.seeking