----John is very -- if he promises to do something he’ll do it .A. gratefulB. stubbornC

问题补充：

----John is very ---- if he promises to do something he’ll do it .

A. grateful

B. stubborn

C. reliable

D. straight

答案：

A. grateful

B. stubborn

(答案→)C. reliable

D. straight

解析：形容词辨析。A感激的；B固执的；C值得信赖的；D直的；句意：—John非常值得信赖。—如果他答应做一件事情，他会做的。故C正确。