我在使用ThenInclude从数据库中获取高级实体时遇到问题。如何更改GetAll方法来做到这一点？

public class Repository<T> : IRepository<T> where T : class
{
    private readonly ApplicationDbContext _db;
    internal DbSet<T> dbSet;
    public Repository(ApplicationDbContext db)
    {
        _db = db;
        this.dbSet = _db.Set<T>();
    }   

    public IEnumerable<T> GetAll(string? includeProperties = null)
    {
        IQueryable<T> query = dbSet;

        if (!String.IsNullOrEmpty(includeProperties))
        {
            foreach (var property in includeProperties.Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries))
            {
                query = query.Include(property);
            }
        }
        return query.ToList();
    }
}

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我是初学者，如果这个问题很愚蠢，我很抱歉。