1.I would let him out every day the weather was nice if he did come.

1.I would let him out every day the weather was nice if he did come.

1.I would let him out every day the weather was nice if he did come.
every day引导时间状语从句；if引导条件状语从句
the weather was nice(状语从句中的主系表结构）
如果他真的来了，每天天气好的时候，我就会让他出去。
2. ... say more than is necessary
这个结构应该来自
I do not wish to complicate the task more than is necessary.
我不想使这项任务比需要的复杂。
个人觉得，这个句子有一点问题。
say more than is necessary
说多过需要（说）的
say more than （it） is necessary更好理解

第一句确认没漏符号或者单词吗，看起来怪怪的
第二句 纯粹是省略了一个what -- say more than (what) is necessary

1,你的分析是正确的，the weather was nice 是定语从句，修饰every day。习惯上，这里是不用关系代词或关系副词，有人认为这里是省略了that。其他类似的结构还有很多，比如：the first time,the instant等。
2.more ...than (is) necessary.固定搭配（意思：超过必要的），如果真的要说省略的，还不如说是省略了it来得适当,即more...than (it) is necessary.追问I appreciate your help