If you use this sentence, you will feel a kind of loneliness gradually. There is nothing outside the yard except jujube trees. There is a sense of loneliness in it. When readers see two trees outside the yard, one is a jujube tree, and they must think that there are other things outside the yard, but they don't. The rest are jujube trees. Very monotonous, very lonely. This feeling of loneliness cannot be expressed by "there are two trees outside the yard".

Another manifestation is dissatisfaction with this loneliness. Lu Xun hoped for fresh social phenomena and "other trees", but he didn't. Lu Xun is looking forward to it.

As far as semantics itself is concerned, Lu Xun has expressed his emotional factors and modality in the first sentence. The analysis is as follows:

Lu Xun did not directly say "there are two jujube trees in my backyard", but divided them into four short sentences, and the last two short sentences were suspected of repetition.

In tone, this is the embodiment of Lu Xun's heavy mentality. When he went out to the backyard, he saw a jujube tree at first sight, then glanced around and saw another jujube tree-this was also the author's idea and was recorded as an objective expression of words. In addition, Lu Xun's tone and words show a slow modality here, which lays the foundation for the following. As if to say: the writer is depressed and needs to come to the backyard to be quiet and find temporary peace!