I have a question about using definite article. I'm Azerbaijanian that's why I don't know English grammar very well. In English lesson our topic was &quot;Article&quot;. And I wanna know can I use &quot;the&quot; with &quot;lunch&quot;, &quot;breakfast&quot; or &quot;dinner&quot;
In most sentences that use the word lunch, I found this word does rarely take the definite article the. For example:     I have lunch in three hours.      Shall we go out for lunch?      Let's have some lunch.      I'll take my lunch to school.   But now I wonder if this word really cannot take the definite article, and if it can, in what cases do I use the definite article and in what cases not?  And also, if the word lunch cannot take the definite article, why cannot it have it?
why can't i select two objects in edit mode?     I am trying to make a face from two different meshes but can't perform the action What is aperture, and how does it affect my photographs? Why does speed of light have to be constant? The Most Efficient Way To Find Top K Frequent Words In A Big Word Sequence Input: A positive integer K and a big text. The text can actually be viewed as word sequence. So we don't have to worry about how to break down it into word sequence. Output: The most frequent K words in the text.  My thinking is like this.    use a Hash table to record all words' frequency while traverse the whole word sequence. In this phase, the key is "word" and the value is "word-frequency". This takes O(n) time.  sort the (word, word-frequency) pair; and the key is "word-frequency". This takes O(n*lg(n)) time with normal sorting algorithm.  After sorting, we just take the first K words. This takes O(K) time.    To summarize, the total time is O(n+nlg(n)+K)， Since K is surely smaller than N, so it is actually O(nlg(n)).  We can improve this. Actually, we just want top K words. Other words' frequency is not concern for us. So, we can use "partial Heap sorting". For step 2) and 3), we don't just do sorting. Instead, we change it to be  2') build a heap of (word, word-frequency) pair with "word-frequency" as key. It takes O(n) time to build a heap;  3') extract top K words from the heap. Each extraction is O(lg(n)). So, total time is O(k*lg(n)).  To summarize, this solution cost time O(n+k*lg(n)).  This is just my thought. I haven't find out way to improve step 1). I Hope some Information Retrieval experts can shed more light on this question. Windows 7 Aero Snap two windows horizontally As many people already know, there are several ways to trigger Windows 7 Aero Snap feature. A user can either press Win+{Left,Right,Up,Down} to snap the window to the left or right or maximize or restore. One can also drag the title bar to all the corner except bottom one.  However, is there any keyboard or mouse shortcut to place one window on top half the screen, and another window on bottom half the screen? Please do not tell me to use "Show Windows Stacked" because if I have more than two windows, it will place ALL the windows horizontally, which is not what I want. I want to be able to select the window I want and place it automatically either on top or bottom half the screen.  Thanks!  Edit: Thanks for Moab's suggestion, both on recommend WinSplit and updating my question.  I should make it more clear that I'm looking for a software that will do the functions WinSplit provided, but with on screen input, such as touch screen or pen. I'm new to Blender and this site, so I apologize in advance if I'm not following any of the proper etiquette.  I'm no artist, but I'm trying to learn Blender so that I have some programmer art for me to work around in Unity.    I followed a tutorial for making a basic human model, I rigged it with rigify, and now I'm starting to export it following yet another tutorial.  The thing is, when I was trying to rig the model, I couldn't get the model to go transparent so that I could see the bones inside the model.  Eventually, I managed to get it into wireframe mode, but I can't get it back into solid mode.    It's probably just a display thing and not a property of the model itself, but I want to be sure.  I'm looking at the display options under the "Figure" pane in Blender, and none of the Display check boxes are checked, including the one that says "Wire".  I don't want to import a plain wireframe model into Unity, and even if that doesn't happen, this is functionality of Blender that I should really know anyway, so I'd appreciate any help that anyone has to offer.  If necessary, I can upload the .blend file, but I'm not sure what site people would prefer that I upload it to. How to use PostgreSQL/PostGIS with ArcGIS for Desktop? MySQL Prepared statements with a variable size variable list How would you write a prepared MySQL statement in PHP that takes a differing number of arguments each time? An example such query is:  SELECT `age`, `name` FROM `people` WHERE id IN (12, 45, 65, 33)   The IN clause will have a different number of ids each time it is run.  I have two possible solutions in my mind but want to see if there is a better way.  Possible Solution 1 Make the statement accept 100 variables and fill the rest with dummy values guaranteed not to be in the table; make multiple calls for more than 100 values.  Possible Solution 2 Don't use a prepared statement; build and run the query checking stringently for possible injection attacks. How do I decrease first byte time with GoDaddy and GitHub pages? Can an illusion give a player partial cover? I'm in an argument with a player at my table, he says hiding behind some bushes while shooting arrows at my monsters gives him partial cover because they can only see his head and shoulders. So they're limited in what they can even aim at. I accepted that. And now he's trying to use minor illusion to create fake bushes/walls and continuing to claim he has partial cover.  I thought cover was based on having a solid obstacle between you and the target... Like, if a magical attack, or penetrating attack can pass through your cover, wouldn't that negate the AC bonus from partial cover? Or is it about "aiming"? What is the variance of the weighted mixture of two gaussians? Say I have two normal distributions A and B with means $\mu_A$ and $\mu_B$ and variances $\sigma_A$ and $\sigma_B$. I want to take a weighted mixture of these two distributions using weights $p$ and $q$ where $0\le p \le 1$ and $q = 1-p$. I know that the mean of this mixture would be $\mu_{AB} = (p\times\mu_A) + (q\times\mu_B)$.  What would the variance be?    A concrete example would be if I knew the parameters for the distribution of male and female height. If I had a room of people that was 60% male, I could produce the expected mean height for the whole room, but what about the variance? \colorbox height too long \documentclass{article} \usepackage[utf8]{inputenc} \usepackage{xcolor} \usepackage{minted} \usepackage{parskip}  \definecolor{codegray}{gray}{0.9} \newcommand{\code}[1]{\colorbox{codegray}{\texttt{#1}}}  \begin{document}  \code{test code}\\ anotherline  \end{document}   This is working good on sharelatex.com and looks like I expect and want it:   but on my local project using this command gives me this:   any idea what could be causing this colorbox height going to the next line? I know in php you are able to make a call like:  $function_name = 'hello'; $function_name();  function hello() { echo 'hello'; }   Is this possible in .Net? Night's Watch deserters are sentenced to death, as we've seen in the very first episode of Game of Thrones. A man dressed all in black is apprehended by Stark men and brought before Lord Eddard Stark. Lord Stark sees him as a deserter and sentences him to die (and then executes that death penalty).  However, there are men of the Night's Watch south of the Wall, on a legitimate mission or on some kind of allowed leave. For instance, we have Benjen Stark visiting Winterfell when the king and his party is there. There is also Yoren, who travels around Westeros in search of new recruits.  I could imagine that the Warden of the North (and other lords in the northern part of Westeros) would have a good idea of who would be allowed further south and whose appearance would raise suspicion. But I reckon the southern lords don't have as many visits from the Night's Watch, so they might not know who would be allowed to be there and who wouldn't.  How would lords who are rather unfamiliar with the specific brothers of the Night's Watch discern deserters from brothers sent out for some reason?  That ends my question, but there is a spoiler from the season 5 finale that continues the question a bit more:      Sam is sent to Oldtown to become a Maester, so he can replace Maester Aemon at Castle Black.  But he is riding together with Gilly (a woman!) and her baby (a baby!), which might raise a lot of suspicion from people who don't know what he is sent out to do.  What prevents southern lords of sentencing Sam as a deserter from the Night's Watch? Review Count - Fix It or Lose It Another meta question identified a bug that was marked as designed. To summarize the bug, the little number that appears next the Review link in the header shows an incorrect value most of the time.         I would like to propose that the feature be dropped. Honestly, I would prefer it be fixed, but the response to the question above gives me little faith that it will be. Half of the time, I click that little brown box and find out that I was lied to. There's nothing to review.  The little number no longer does the job it was created to do.        Oh sweet! Three things I can review!        Just kidding... Deriving the conditional distributions of a multivariate normal distribution We have a multivariate normal vector ${\boldsymbol Y} \sim \mathcal{N}(\boldsymbol\mu, \Sigma)$. Consider partitioning $\boldsymbol\mu$ and ${\boldsymbol Y}$ into  $$\boldsymbol\mu = \begin{bmatrix}  \boldsymbol\mu_1 \\  \boldsymbol\mu_2 \end{bmatrix} $$ $${\boldsymbol Y}=\begin{bmatrix}{\boldsymbol y}_1 \\  {\boldsymbol y}_2 \end{bmatrix}$$  with a similar partition of $\Sigma$ into $$  \begin{bmatrix} \Sigma_{11} &amp; \Sigma_{12}\\ \Sigma_{21} &amp; \Sigma_{22} \end{bmatrix} $$ Then, $({\boldsymbol y}_1|{\boldsymbol y}_2={\boldsymbol a})$, the conditional distribution of the first partition given the second, is  $\mathcal{N}(\overline{\boldsymbol\mu},\overline{\Sigma})$, with mean $$ \overline{\boldsymbol\mu}=\boldsymbol\mu_1+\Sigma_{12}{\Sigma_{22}}^{-1}({\boldsymbol a}-\boldsymbol\mu_2) $$ and covariance matrix $$ \overline{\Sigma}=\Sigma_{11}-\Sigma_{12}{\Sigma_{22}}^{-1}\Sigma_{21}$$  Actually these results are provided in Wikipedia too, but I have no idea how the $\overline{\boldsymbol\mu}$ and $\overline{\Sigma}$ is derived. These results are crucial, since they are important statistical formula for deriving Kalman filters. Would anyone provide me a derivation steps of deriving $\overline{\boldsymbol\mu}$ and $\overline{\Sigma}$ ? Thank you very much! How do I calculate the distance of an object in a photo? How does friction stop a car? I'm unable to understand how friction causes motion in cars and also is responsible for stopping them. When it starts the impending motion of tyres is in the backward direction that's why friction is in the forward direction and the car starts moving. But when the car engine turns off, the car stops after some time, but the condition of tyres are the same as in the previous case and friction must be in the forward direction. Minimize absolute values of errors instead of squares When I launch nautilus from terminal the following error is printed and nautilus doesn't open up.  (nautilus:25179): GLib-GIO-CRITICAL **: g_dbus_interface_skeleton_unexport: assertion 'interface_-&gt;priv-&gt;connections != NULL' failed  (nautilus:25179): GLib-GIO-CRITICAL **: g_dbus_interface_skeleton_unexport: assertion 'interface_-&gt;priv-&gt;connections != NULL' failed Could not register the application: Timeout was reached  (nautilus:25179): Gtk-CRITICAL **: gtk_icon_theme_get_for_screen: assertion 'GDK_IS_SCREEN (screen)' failed  (nautilus:25179): GLib-GObject-WARNING **: invalid (NULL) pointer instance  (nautilus:25179): GLib-GObject-CRITICAL **: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed   What could be the problem??