- I am glad to be invited to Tom’s birthday party on Friday evening Mum. yourself

问题补充：

--- I am glad to be invited to Tom’s birthday party on Friday evening, Mum.

--- yourself, dear! But remember to be back before 10 o’clock.

A. HelpB. Make C. Enjoy

答案：

解析：句意:-妈妈，我很高兴被邀请去参加周五晚上Tom的生日晚会。-亲爱的，玩得高兴点。但是要记得在10点之前回来。help yourself，随便吃、喝；enjoy yourself 玩得高兴；make yourself 随便，随意。根据这里的情景，Tom要去参加生日晚会，故应是祝他玩得高兴。故选C。