学习资料
[意 思]adj. 棘手的,费劲的
[例]  That was tough work. 那是棘手的工作。
adj. 严格的,强硬的
[例]  The law is tough on offenders.
该法律对违法者处罚很严厉。
adj. 健壮的,结实的
[例]  A mountain climber must be tough.
登山运动员必须身体健壮。
adj. (肉等)老的,咬不动的
[例]  The steak was so tough I couldn't eat it.
牛排太老了,我咬不动它。