The land and forests encompassing Amon Lac appear to have been constantly part of the realm of the Silvan Elves from the start of the First Age until the second millienium of the Third Age. Aside from some bands of woodsmen, the race of Men seem to have avoided, or at least ignored the area, as it lay outside the reach of Numenor (later, of Gondor or Arnor). The same seems true of the Dwarves, who besides building a trade road through, preferred to stay in their mountain halls.  Then suddenly into the tale appears the Fortress of Dol Guldur Was it a mini-Barad-Dur, or a hole in the ground there lived a corrupted Maiar? It IS described as a 'fortress', it had dungeons, and was large enough to serve as a garrison for a force of orcs strong enough to threaten both Lorien and the Woodland Realm simultaneously. Did Sauron and his servants construct a new entity, or simply occupy an existing one dating from earlier history?
Who built the fortress of Dol Goldur, and when was it built? And was it always a place for evil, or Sauron just occupied it?  Despite the fact that Mordor is much better fortified; artificially by the old fortifications,  and geographically, as it is surrounded by the mountains. Also considering the presence of mount doom that seem to enhance Sauron's power, Sauron chose to start his campaign from Dol Goldur, despite Mordor being ready for quite some time.  Why did he choose this enigmatic fortress, and not go straight for Mordor or even go earlier?
When is the past perfect exactly needed? I have never had this problem before. But after seeing some questions posted on ELU, I started to doubt. I have been through links1, pages of grammar books2, a lot of questions3 posted here and ELU. I now still can't seem to understand how the past perfect is exactly used. The references sometimes even contradict each other.  What I had understood so far was      The past perfect is not necessary if we are not 'going back' to the earlier past, and simply moving from one event to another.   but I then saw a lot of other 'rules' including      If the sequence is clear, the past perfect is not needed.   which is slightly different, less 'narrow' and can be applied in more situations than the first ruleA, and      The past perfect is optional only when talking about an action at a specific time.   This is confusing. Can anyone here clarify things out please?    A For example, for  Doing the survey [completed] -&gt; Showing the result      We showed the result of the survey we did.      If the second rule is applied, the sentence above is fine (the sequence is clear), but not if the first rule since we are not moving from any event to the next and possibly even going back.    1  and   2 Practical English Usage (2005) by Michael Swan, Collins Cobuild Student's Grammar (1991). Upper-Intermediate Cutting Edge.  3 including , , ,  etc. How does long to int cast work in Java? How can I get the Cartesian product (every possible combination of values) from a group of lists?  Input:   somelists = [    [1, 2, 3],    ['a', 'b'],    [4, 5] ]   Desired output:  [(1, 'a', 4), (1, 'a', 5), (1, 'b', 4), (1, 'b', 5), (2, 'a', 4), (2, 'a', 5) ...] There are several spells that require the target to be "humanoid" such as , , etc.  However, if the target is Polymorphed after that spell has been successful, then what happens?  Does the change in form to Beast end the spell effects? Does it suppress the spell until the correct form returns? Does it do something else? Remove all content using pure JS Producing PDF/X compliant document with XeLaTeX I came across this example when trying to mount a usb device inside a openvz container and I have never seen the construct in the second line before. Can you explain what it signifies?  #!/bin/bash . /etc/vz/vz.conf Can we really not tell if we are moving? It has been a while since I've thought about physics, however, I remember something about how if you are on a train with no windows that is going perfectly straight and is perfectly smooth, there is no experiment that you could perform to prove that you are in motion or at rest. So I have a couple of questions related to this.   Is this still held to be true? I was just wondering if anything in physics has come to light since I learned about this (about 10 years ago) that would allow an observer on the train to tell if they are moving. If this is true, why couldn't you accelerate a particle in different directions to a certain mass and measure how much energy it took to get it up to that mass. If you were moving in any direction, wouldn't you measure less energy in your direction of travel? Would having an outside observer affect the aforementioned experiment in any way? Is there a filesystem that is "friendly" to both windows and Linux? Regex to get string between curly braces Mac equivalent of Ctrl + Space to select an item on a list I want to select non-consecutive items on a list, without using a mouse/trackpad - there should be no clicks involved.  In Windows and Linux (at least Ubuntu) an item can be selected using Space/ button, which, in combination with arrows and Ctrl key allows me to select multiple items in any environment (file manager, IDE etc.) - e.g.  Enter a directory -> hold Ctrl -> down arrow twice -> press Space -> down arrow twice -> press Space.  Now I should have items 1, 3 and 5 selected. Is there a way to do the same thing in OS X?  PS. Sorry for such a verbose description, but so far every answer I encountered advices using Command + Click, and this is something I don't want to do. Dirac Delta or Dirac delta function? How many String objects will be created when using a plus sign? I have a Windows 8 (64-bit, not Pro) machine, and I want to limit the Internet bandwidth available to Windows Update. I read about BITS and GPMC methods, but I don't know how to open the BITS window, and GPMC seems like a Windows Server feature.  How can I control how much bandwidth is available to Windows Update and BITS? Counting overlapping polygons in GeoJSON to result in new set of polygons? Custom cross-reference formats (e.g. "Equation 1" instead of just "1") How do I import a Python module given its relative path?  For example, if dirFoo contains Foo.py and dirBar, and dirBar contains Bar.py, how do I import Bar.py into Foo.py?  Here's a visual representation:  dirFoo\     Foo.py     dirBar\         Bar.py   Foo wishes to include Bar, but restructuring the folder hierarchy is not an option. How exactly to compute the ridge regression penalty parameter given the constraint? The accepted answer in  does a great job of showing that there is a one-to-one correspondence between $c$ and $\lambda$ in the two formulations of the ridge regression: $$ \underset{\beta}{min}(y-X\beta)^T(y-X\beta) + \lambda\beta^T\beta $$ and  $$ \underset{\beta}{min}(y-X\beta)^T(y-X\beta) \text{ s.t. }\beta^T\beta\leq{c} $$  The linked answer shows this in the orthogonal case.    In a general (non-orthogonal case), how can I compute $\lambda$ from $c$?  Update Here is an answer for going from $\lambda$ to $c$:   Assuming that the coefs are constrained by the penalty, $$ \beta^T\beta = c $$ and  $$ \beta = (X^TX + \lambda I)^{-1}X^Ty\\ \beta^T\beta = c = \beta^T(X^TX + \lambda I)^{-1}X^Ty $$  Still working on going the other way What UML (Unified Modelling Language) tools are available? I tried to write , but I couldn't find any simple explanation page to link to. I ended up garbling a home-spun description of my own with a not-terribly-helpful image from 2012.  This  puts it better than I can:     As a new user in 2015 can there please be more information about what is WinterBash. The link took me to a bunch of stick figures running around making (I think) numbers (I think its a countdown clock). It doesn't explain the event or even what a hat is. – Ian Miller Dec 4 at 2:58   All I found on Meta was dead links. For example,  was downvoted to -2 and answered with a link to an FAQ page that no longer exists.