I want to know the difference between 'I know swimming.' and 'I know to swim.' Do native speakers understand the meaning of the sentence 'I know to swim.' I didn't see the sentence like 'I know to swim.' but I think that(I know to swim) is a right sentence grammatically. Is the sentence (I know to swim.) not acceptable but understandable by a native speaker?
I was reading a website where common English sentence errors are written -     INCORRECT - He doesn't know to swim.      CORRECT - He doesn't know how to swim.   I know He doesn't know how to swim is a correct sentence. But why is the other one wrong, is my question?  I know that know is a transitive verb. So, the following are correct -   i) He knows swimming.  Swimming is a gerund. We can also use the infinitive form here - to swim  ii) He knows to swim.
How to change default action for file types? There is a certain text editor that I would like to set as the default editor for certain file types but if I try selecting it on the “Open With…” menu, that does not work. However, it has put an explorer context menu item in, which does work. How could I make this menu item the default double-click action, for certain file types?  Thank you SSRT and Josh R. Both good answers. It's a pity I can't give you both best answer.  For what it's worth, I found the answer today (twenty-four hours after asking this question). How many physical degrees of freedom does the $\mathrm{SU(N)}$ Yang-Mills theory have? The $\mathrm{U(1)}$ QED case has two physical degrees of freedom, which is easy to understand because the free electromagnetic field must be transverse to the direction of propagation. But what are the physical degrees of freedom the $\mathrm{SU(N)}$ Yang-Mills theory?   I believe that the $\mathrm{SU(N)}$ Y.M. theory has four degrees of freedom, and it is easy to see that by gauge fixing (such as the Lorentz condition or the Coulomb condition) that we can always remove one redundant degree of freedom. But then we still haven't completely fixed the redundant degrees of freedom. Thus my question is:     How many physical degrees and how many are redundant degrees of freedom does the Y.M. theory have?    I would be interested to understand how we can determine this mathematically, and also to understand what the physical intuition behind this is? I'm a web developer, started to become a web designer. However, I think my understanding of colors is not practical yet. There are tools out there that can give you color harmonies, and more stuff, like , but they don't give you the start point. I mean, how should I know that for this web site, I'd better use green and for that website, choose red. How should I know that?  I think color selection is more like an art, instead of being a science, and I'm like "you should become an color artist, in order to become a web designer".  How can I improve my color selection skill? What is the meaning of “runneth”? What is the meaning of “runneth” in ? How can I use "." as the delimiter with String.split() in java Complicated FOR loop nesting. Having trouble cleaning up legacy code I am trying to tidy up some really bad legacy code from an old developer and I'm trying to get rid of these nested for loops. The code below shows what I'm currently working with. I've fixed this before with nested SOQL queries but nothing like this. How would this need to look to remove these for loops (except Trigger.New)? Would I use Maps? How would I do that?  map&lt;Id,SObject&gt; mapProperyIdBudDetail = util.GetObjFields(setPropertyId, 'Property'); map&lt;Id,SObject&gt; mapSpaceIdBudDetail = util.GetObjFields( PropertyMap.keyset(), 'Space');  for ( Lease__c l: Trigger.New ) {      if(mapProperyIdBudDetail.get(PropertyMap.get(l.space__c))!=null) {          lProperties = new List&lt;SObject&gt;{mapProperyIdBudDetail.get(PropertyMap.get(l.space__c))};              for ( SObject p: lProperties ) {                  for ( String fm: FieldMap.keyset() ) {                      if ( p.get(FieldMap.get(fm)) != Null) {                         l.put(fm,p.get(FieldMap.get(fm)));                     }                  }             }     } } What does 'Ign' , `Get` or 'Hit' mean when running an apt-get update? I had a bunch of errors in the output of sudo apt-get update:  duplicate entries and 404 not found errors.  Figured those out, I hope: I removed PPAs that didn't have any packages associated with them, then I removed out a duplicate entry in /etc/apt/sources.list.  It seems I have royally buggered it up.  Now most of the lines say Ign when I do sudo apt-get update.  How do I go about straightening out what I have screwed up?  I need to get rid of these Igns that are all over the place.  There are about 50% (eyeball guess) Igns! What's /System/Volumes/Data? New mac user here (Linux background). I'm running macOS Catalina (Beta5). I've noticed there are 5 volumes in my main disk container. One is mounted at /, that I understand, it's the system, another is /System/Volumes/Data, which I tough it would be the Linux /home, but it's not, so what it it?  Also what are the other two unmounted volumes? One might be the recovery one, but the other? Thanks! C++ guarantees that variables in a compilation unit (.cpp file) are initialised in order of declaration. For number of compilation units this rule works for each one separately (I mean static variables outside of classes).  But, the order of initialization of variables, is undefined across different compilation units.  Where can I see some explanations about this order for gcc and MSVC (I know that relying on that is a very bad idea - it is just to understand the problems that we may have with legacy code when moving to new GCC major and different OS)? How do I send a file with FileZilla from the command line? I have a batch file that builds an application, and then I want to upload it to an FTP server from the command line.   Considering I do the upload manually with , is there a command line for it to upload files?  I am limited to Windows. JavaScript YAML Parser I saw many saying that the latest version of Ubuntu 16.04 includes an opensource driver for ATI. I have an HP laptop with AMD 6770m + Intel HD 3000 hybrid graphics and wants to install Kubuntu on it. I created a bootable USB drive of Kubuntu 16.04 and booted from it just to check everything works perfectly (I don't want to install it separately and ruin bootloader as of now). But my laptop is getting too hot and the battery is not lasting for more than 30 mins. Also the brightness control is not working at all and it stays high always.   How can I get hybrid graphics on Kubuntu/Ubuntu working well? I am ready to turn off the ATI card since I am not going to play any games on Linux. I just need the Intel graphics + Cool Laptop + Good battery Life + Brightness control.  My BIOS setting for switchable graphics mode is FIXED. Do I need to change it to DYNAMIC?  UPDATE  I wasn't able to make things work in 16.04 so installed 14.04 LTS along with the AMD Catalyst driver. Now everything works perfectly fine. Below are the steps.   Clean install Ubuntu 14.04 LTS Install the fglrx catalyst drivers using “Additional Drivers” window. This will enable us to switch graphics Restart Ubuntu FAN Noise Fix - Refer this  and install i8kutils Brightness Control - Check this     is the official documentation for AMD/Intel hybrid graphics Sometimes I found that writing just "J. Doe" may lead, in a justified line with few words, to a big space between the initial and the surname. Using J.\,Doe looks ok but I would like to know if there is a general rule for spacing between initials and surnames. What is the CVE-2014-6271 bash vulnerability (Shellshock) and how do I fix it? At 9th level, the Armorer Artificer (from Tasha's Cauldron of Everything) gains the &quot;Armor Modifications&quot; feature :  You learn how to use your artificer infusions to specially modify your Arcane Armor. That armor now counts as separate items for the purposes of your Infuse Items feature: armor (the chest piece), boots, helmet, and the armor’s special weapon. Each of those items can bear one of your infusions, and the infusions transfer over if you change your armor’s model with the Armor Model feature. In addition, the maximum number of items you can infuse at once increases by 2, but those extra items must be part of your Arcane Armor.  This special weapon is called 'Thunder Gauntlets' (a simple melee weapon) for the 'Guardian' Armor Model, and 'Lightning Launcher' (a simple ranged weapon) for the 'Infiltrator' Model. But I am wondering which Artificer Infusions are appropriate for this special weapon ? Is it only the 'Enhanced Weapon' and 'Radiant Weapon' infusions, or are there others ? Integral of $\frac{\sqrt{x^2+1}}{x}$ So I have to do the integration of $\frac{\sqrt{x^2+1}}{x}$. Give me a hint. What should I replace? Should I do it with integration by parts? I don't follow understand what this theorem is saying: "Every function $f: A \to{\cal P}(A)$ is not surjective."   Is this saying so for example let A = {1,2,3} then the power set of A is {},{1},{2},{3},{1,2},{1,3},{2,3},{1,2,3} Is this saying that there is no surjective function that takes every element in each of its power sets to atleast 1 element in A?  Is my understanding correct? Splitting a semicolon-separated string to a dictionary, in Python I have a string that looks like this:  "Name1=Value1;Name2=Value2;Name3=Value3"   Is there a built-in class/function in Python that will take that string and construct a dictionary, as though I had done this:  dict = {     "Name1": "Value1",     "Name2": "Value2",     "Name3": "Value3" }   I have looked through the modules available but can't seem to find anything that matches.    Thanks, I do know how to make the relevant code myself, but since such smallish solutions are usually mine-fields waiting to happen (ie. someone writes: Name1='Value1=2';) etc. then I usually prefer some pre-tested function.  I'll do it myself then. Why do I only have 30V going to my light fixture How do I get console output in C++ with a Windows program?