Programming Nagios Dependancies

I have read a few sources of Nagios documentation, and am still confused about the establishment of dependancies.
Q1: If a host is "down", will the notification for the services listed under the down host still be done?
Q2: How do I make a service dependent on a host being up/down. I see lots of examples for inter-service dependancy but do not see this particular case.
Q3: Do I have to define a host/service dependancy record for each and every service I need to have a dependancy, or can a dependancy record list several hosts and services to which it is dependant?
I only ask these questions because I have several thousand service points and several hundred hosts. And based on the some of the examples I have see, it looks like it could be a chore.
Thanks
Q1: If a host is "down", will the notification for the services listed under the down host still be done?
Q2: How do I make a service dependent on a host being up/down. I see lots of examples for inter-service dependancy but do not see this particular case.
Q3: Do I have to define a host/service dependancy record for each and every service I need to have a dependancy, or can a dependancy record list several hosts and services to which it is dependant?
I only ask these questions because I have several thousand service points and several hundred hosts. And based on the some of the examples I have see, it looks like it could be a chore.
Thanks