阅读理解。

     John and David are students. They are Mr. Green's sons. They get up early in the morning. They go

to school by bus after breakfast. Sometimes they have lunch at school. John likes hamburgers, chicken

and eggs. David likes vegetables and fruit. After lunch John goes to play volleyball and David goes to the

classroom. John likes playing computer games, but David likes singing.

根据短文内容，判断下列句子正（T）、误 （F）。

1. John is a student and David is a teacher.

2. Mr. Green is John and David's father.

3. John and David have lunch at home every day.

4. John likes vegetables and fruit.

5. David likes singing and John likes playing computer games.

普萘洛尔在人体中有4-羟基普萘洛尔和萘氧乳酸二个主要代谢物，后者没有药理作用，前者与普萘洛尔有同样的药理作用。当普萘洛尔静脉注射时，血液中没发现4-羟基普萘洛尔，而口服时却在血中检测到几乎相同浓度的普萘洛尔和4-羟基普萘洛尔，这主要因为

A．普萘洛尔有首过现象

B．普萘洛尔有肠肝循环

C．普萘洛尔代谢有饱和性

D．普萘洛尔代谢酶有酶诱导和酶抑制现象

E．普萘洛尔代谢受饮食影响