单项选择题
A．who their trainers are B．they will be praised by their trainers C．they will get a reward D．something dangerous will happen to them
A．childish B．difficult C．not enjoyable D．worthwhile
A．only remembers one of Jack’s seventeenth birthdays B．always sends Jack something on his birthday C．has forgotten all of Jack’s birthdays D．has forgotten Jack’s seventeenth birthday