我来尝试回答你吧.
Dear Sir/Madam
Thank you for your last letter.As for your suggestion, i feel it's ok. By the way, it's my pleasure for the company to offer me the opportunity to attend the interview.
如果你想说约定时间,你可以这样表述:Let's fix a date, IS this friday ok?
Best Regards
Shelly(填写你的英文名)
PS:其实这样的回信,不需要过于正式的范文吧,只需要表达清楚自己的意思就好~~~我想你收到的是外企的邮件回复吧.