Spanish language Q&A Forum

In the example, "You have already slept enough for today," what is the reason for using 'lo' here: "Ustedes ya han dormido lo suficiente por hoy."

Hola, 

I never received a reply to my 2nd question below, it starts like this:

"Hello Inma,

Thank you so much for your patience and reply.

I was wondering, is there a way I can find my questions and answers received within my page....."

see below for the full question, thank you.

I'm not great at grammar in my own language and before I started learning Spanish I didn't even know what the subjunctive was. So I've learned it's a sort of feeling expressing doubt or IF something were to happen or wishing? I can't quite see how "we're going to sit where there is shade" fits in the subjunctive. Doesn't it suggest certainty? Or am I wrong about this?

The lesson says  "Remember that when you use this structure with an adjective, the adjective must agree with the subject." but none of the examples actually demonstrate this. It might be a good idea to throw in some feminine and plural adjective examples to more explicitly demonstrate the agreement!