SELECT  ...
FROM    Customers
        LEFT JOIN Orders ON Customers.Id = Orders.CustomerId
        LEFT JOIN Goods ON Orders.Id = Goods.OrderId
WHERE   Customers.Id IN (1,2,3)

from customer in db.Customers
join order in db.Orders on customer.Id equals order.CustomerId
into orders
from order in orders.DefaultIfEmpty()
select new { customer, order }
into customerOrder
join good in db.Goods on customerOrder.order.Id equals good.OrderId
into orders
from order in orders.DefaultIfEmpty()
select new { customerOrder.customer, customerOrder.order, good}
into customerOrderGood

from customer in db.Customers
join ord in
	(from order in db.Orders
	join gd in
		(from good in db.Goods
		join model in db.Models on good.Id equals model.GoodId
		into models
		select new { good, models }) on order.Id equals gd.good.OrderId
	into goods
	select new { order, goods }) on customer.Id equals ord.order.CustomerId
into orders

from customer in db.Customers
join order in db.Orders on customer.Id equals order.CustomerId
into orders
from order in orders.DefaultIfEmpty()
select new { customer, order }
into customerOrder
join good in db.Goods on customerOrder.order.Id equals good.OrderId
into goods
from good in goods.DefaultIfEmpty()
select new { customerOrder.customer, customerOrder.order, good}
into customerOrderGood