I can’t say which type of tea tastes better. It’s just a(n) ______ of personal preference.

 As nobody here knows what is wrong with the machine, we must send for an engineer to _______ the problem.

(2012·江苏)—Can I help you with it?—I appreciate your ________，but I can manage it myself.

-- What impressed you most during your stay in Britain? -- I had the _____ of meeting the Queen when she visited our school.

The team has worked hard and its efforts have been _______with success.