He was (weary) of the constant battle between them.()

单项选择题Which of the following tells us how caffeine affects sleep()

A. Caffeine blocks production of the enzyme that stops melatonin production.
B. Caffeine interrupts the flow of the hormone that prevents people from sleeping.
C. Caffeine halves the body’s levels of sleep hormone.
D. Caffeine stays in the body for many hours.

单项选择题Which of the following statements is NOT true according to the passage()

A. Tile pressure changes in the sand bed are the most important factor in the creation of beach.
B. The crest pushes water seaward.
C. People take it for granted that waves carry water and sand to the beach.
D. The high pressure under a crest forms strong whirlpools above the sand.

单项选择题52（）

A.ought
B.added
C.used
D.led

单项选择题Google provides a mapping service online.

单项选择题53（）

A. away
B. as many as
C. out
D. as much as