请帮我分析和翻译下面句子： I took it for granted that you would stay with us.

I took it for granted that you would stay with us.
1. that从句用作took的宾语；
2. take it for granted是习惯用语，意思是“认为理所当然”其深层语法结构是复合宾语，it是形式宾语，代替拖后的that宾语从句，for granted是介词短语作宾语补足语；
直译：我把你与我们呆在一起认为是理所当然的事。

Mechanical advantage is the number of times the resistance forces is greater than the efforts.
1. 主句:Mechanical advantage is the number of times greater than the efforts；
2. 定语从句：the resistance forces is，先行词是the number，关系代词that省略；
3. be times greater than ...比...大数倍；
翻译：机诫效益是阻力对所施加力的数倍

补充回答。

你的理解“认为理所当然应该在一起”有些偏差，如果是那样的话，后面的that从句应该用虚拟语气，即：
I took it for granted that you should have stayed with us.（这里因为是对过去的虚拟，所以用should have stayed表示，意思是“本应该在一起”，言外之意不在一起。）
但是原句中主句和从句都是过去时态，依然是真实语气，所以实际上还会在一起的。事实上本句表达的是：你那时会和我们在一起，我当时认为这是理所当然的事。

take it for granted认为..理所当然
I took it for granted that you would stay with us 我觉得你和我们在一起是理所当然的。

Mechanical advantage is the number of times the resistance forces is gr