This particular statement is neither correct nor wrong. Dogs do not understand English or any other language that human beings speak, but they do understand certain words, phrases, or sentences which are used on a regular basis. For instance, if the dog is offered food by saying that “Come and have some food”, it might not understand the whole sentence, but as the word ” food” is used on a regular basis, it can connect it with something to eat.
Furthermore, it also depends upon our way of saying and the tone. Depending on the tone used, dogs can actually derive what we are trying to convey to them. They can associate our tone of saying with a certain kind of behaviour if it is of anger, love, or kindness. Dogs can also understand our body language and depending upon it, they can grab our moods and thoughts. Hence, it can be said that dogs can understand a language, but not wholly.