1. —What was the party like? = How was the party? 聚会怎么样？
—Wonderful. It's years since I enjoyed myself so much. 好极了。我已经多年没有这么高兴了。（It's + 一段时间 + since... 意思是“自从......以来，已经有多久了”，since 引导时间状语从句。）
2. It is because he is kind and modest that he wins the respect of others.
这是含有 It is...that... 强调结构的句子，被强调的是原因状语从句 because he is kind and modest，全句的意思是：是因为他友善和诚实，他赢得了别人的尊敬。