Let's leave our work behind us.这句话什么意思，behind us怎么解释？

Question

My mother knows all there is to know about taking care of babies,I assure you.这里的knows all there is to know about结构看不懂。
He made the weekend very easy for us to enjoy.这句话的结构分析一下

She kisses him and Susan good-bye.这里good-bye是补语吧？

Please look in the car for the sleeping bag.I'm afraid that we (might not have or may not have) remembered to take it.为什么这里不能用could not have？

Answer 1

knows all there is to know about 是一个宾补结构，用来解释all ，这句话的意思是，我确信我妈妈知道所有关于照顾孩子的东西
He made the weekend very easy for us to enjoy 是 make 的一个结构，但这种结构不太常见，意思是他很容易地让我们享受这个周末
Susan good-bye 我自己认为是 say good-bye ，这是两句话，她亲吻了他然后说再见
could not have 主观性太强 may or might 表示有这种可能性，意思是 在车里看好我们的睡袋，我担心我们可能会忘记拿它。可能要用might 或may
Let us leave our work behind us leave ...behind 固定搭配 把。。。放下 这句话的意思是 现在把我们的工作放下。