问道单选

1A 主句是Sam is being taken good care of in the town.而as well as other chidren who have no parents是一个定语从句，所以根据主语来确定谓语动词是用单数还是复数。
2C 他们五年没有见过了。可以用It has been现在完成时或者是It is一般现在时。因为只是陈述一个事实，所以排除A B D.

Sam as well as other children who has no parents is taken good care of the town.
C.has;is taken

It had been five years since they last saw each other.
B.had been

A定语从句主语是children，sam是主句主语，他在城市里被照顾的很好。
B从上次见面到现在所持续的时间

1.选A。
因为这其实是一个包含定语从句的单句，who____no parents的先行词是other children，所以要用复数have，而又由于前面as well as 遵循就远原则，所以take care 和Sam之间才是动宾关系，因而后面的空用单数。
2.选B。
A、C、D都肯定不对，不过B也不太好，如果有has been的话，就最好了，现在只能用B。