(real不能用来修饰表示人的名词．)
true可表示“忠诚的”，而real不能表示这一意思．如：
6. A true friend will always help you. 忠诚的朋友会永远帮助你．
7. He is always true to his friends. 他总是忠实于他的朋友。
m. be worth
adj. 不能单独使用, + n. / -ing (不能接不定式 )
be worth doing sth. (动宾关系, 但不能用被动)
1. The necklace was worth 500 francs at the most. 那条项链最多值500法郎。
2. The work is worth our while / the trouble.
我们的精力是值得花在这项工作上的。干这项工作麻烦一点是值得的。
3. The car isn't worth repairing. 这辆汽车不值得一修。
( 不能说..to repair, to be repaired 或 being repaired )
4. She's not worth getting angry with. 犯不上跟她生气。
5. The article is well worth reading. 那篇文章很值得—读。
[注]这种结构中的动词—ing形式在逻辑上与前面的主语具有动宾关系。但该动词不能用被动形式，不能说The car isn't worth being repaired．
[注]应该用well修饰worth，不能用quite，very或very much等修饰worth，
如句⑤。再如：It's well worth trying.(很值得-试。)
不能说It's very／quite worth trying．
* 用引导词it作“worth的主语，这种用法可与上一种用法互换使用。如：
6. It isn't worth repairing the bike. = The bike isn't worth repairing. 这辆自行车不值得修。
7. It isn't worth getting angry with her.= She's not worth getting angry with.犯不上与她生气。
8. It's worth visiting the park a second time. = The park is worth visiting a second time.
那公园值得再去一次。
9. Don't get the box down. It isn't worth it. = worth the trouble.
worthless = valueless 毫无价值
valuable = priceless 非常贵重, 无价之宝