Java Random Sentence Generator Class not working in Runner

Question

I am trying to make a program in VScode, utilizing Maven Java, that generates sentences randomly through randomized words for each part of speech, randomized punctuation, randomized sentence structure, etc. I have a parent class called SentenceGen which contains all of the arrays and some methods to pull random words/punctuation (e.g. getNoun, getVerb). For your convenience I've removed the words in the larger arrays:

import java.lang.Math;

public class SentenceGen{
    
    //an array of a lot of nouns found at https://gist.github.com/ijmacdowell/8325491
    protected static String n[] =  {""};
    
    //an array of verbs found at https://gist.github.com/ijmacdowell/8325491
    protected static String v[] = {""};

    //an array of adverbs found at https://grammaran.com/wp-content/uploads/2021/09/pp-parts-of-speech.pdf
    protected static String adv[] = {""};
    
    //an array containing each of the three existing articles
    protected static String art[] = {"the", "a", "an"};

    //an array containing common pronouns
    protected static String pro[] = {"they", "them", "it", "he", "him", "she", "her", "their", "we", "I", "his"};
    
    //an array containing common prepositions
    protected static String prep[] = {""};
    
    //an array containing coordinating conjuctions
    protected static String coordConj[] = {"and", "or", "but", "for", "nor", "yet", "so"};

    //an array containing subordinating conjunctions for even more complexity
    protected static String subConj[] = {""};

    //default constructor 
    public SentenceGen(String n[], String v[], String adj[], String adv[], String art[], String pro[], String prep[], String coordConj[], String subConj[]){
        SentenceGen.n = n;
        SentenceGen.v = v;
        SentenceGen.adj = adj;
        SentenceGen.adv = adv;
        SentenceGen.art = art;
        SentenceGen.pro = pro;
        SentenceGen.prep = prep;
        SentenceGen.coordConj = coordConj;
        SentenceGen.subConj = subConj;
    }

    //gets a random noun from the noun array
    public String getNoun(){
        int a = (int)(Math.random()*(SentenceGen.n.length-1));
        return SentenceGen.n[a];
    }
    //gets a random verb from the verb array
    public String getVerb(){
        int a = (int)(Math.random()*(SentenceGen.v.length-1));
        return SentenceGen.v[a];
    }
    //gets a random adjective from the adjective array
    public String getAdj(){
        int a = (int)(Math.random()*(SentenceGen.adj.length-1));
        return SentenceGen.adj[a];
    }
    //gets a random adverb from the adverb array
    public String getAdv(){
        int a = (int)(Math.random()*(SentenceGen.adv.length-1));
        return SentenceGen.adv[a];
    }
    //gets a random article from the article array
    public String getArt(){
        int a = (int)(Math.random()*(SentenceGen.art.length-1));
        return SentenceGen.art[a];
    }
    //gets a random pronouns from the pronouns array
    public String getPronouns(){
        int a = (int)(Math.random()*(SentenceGen.pro.length-1));
        return SentenceGen.pro[a];
    }
    //gets a random prepositions from the prepositions array
    public String getPrep(){
        int a = (int)(Math.random()*(SentenceGen.prep.length-1));
        return SentenceGen.prep[a];
    }
    //gets a random coordinating conjuctions from the coordinating conjuctions array
    public String getCoordConj(){
        int a = (int)(Math.random()*(SentenceGen.coordConj.length-1));
        return SentenceGen.coordConj[a]; 
    }
    //gets a random subordinating conjunctions from the subordinating conjunctions array
    public String getSubConj(){
        int a = (int)(Math.random()*(SentenceGen.subConj.length-1));
        return SentenceGen.subConj[a];
    }
    //randomizes what tense the verb is in (and does it in a grammatically correct way)
    public String getTense(){
        int a = (int)(Math.random()*2);
        if(a == 0){
            return getVerb();
        } else {
            String x = getVerb();
            if(x.substring(x.length()-2, x.length()-1).equals("e")){
                return (x + "d");
            } else {
                return (x + "ed");
            }
        }
    }
    //punctutation generation
    public String getPunct(){
        int x = (int)(Math.random()*2);
        if(x == 0){
            return "";
        } else {
            int a = (int)(Math.random()*3);
            if(a == 0){
                return ".";
            } else if(a == 1){
                return "?";
            } else if(a == 2){
                return "!";
            } else {
                return " <p>Something went wrong, please try again</p> ";
            }
        }
    }
}

I have a child class of SentenceGen called simpleSentence (to generate several simple sentences). I know there are probably several problems with my approach to the program in general but the goal is to make an ArrayList of simple sentence structures and pull one randomly:

import java.util.ArrayList;
import java.math.*;

public class simpleSentence extends SentenceGen{
    //creates an arraylist containing all simple sentence structures
    private ArrayList<String> sSentence = new ArrayList<String>();
    sSentence.add(getArt + " " + getNoun + " " + getTense + " " + getArt + " " + getNoun + getPunct);
    sSentence.add(getPronouns + " " + getTense + getPunct);

    //constructor
    public simpleSentence(ArrayList<String> sSentence){
        super(n, v, adj, adv, art, pro, prep, coordConj, subConj);
        this.sSentence = sSentence;
    }

    //pulls a random sentence structure
    public String toString(){
        int a = (int)(Math.random()*(sSentence.size()-1));
        return sSentence.get(a);
    }
}

The problem is that I can't call the simpleSentence class in my runner class and I don't know how to approach this. Should I make the simpleSentence a package and import it into the runner? Another note is that they are all src files and because this is my first time using VScode I don't know if that effects the outcome or anything like that. Thanks in advance!