This is a picture/photo in which there are two birds. This is a picture/photo.There are two birds in it. 以上两句指照片中有两只鸟. This is a picture/photo on which there are two birds. This is a picture/photo.There are two birds on it. This is a picture/photo and two birds are on it. 这几句则表示有两只鸟站在这张照片上.