About chemical molecular structure models

This question is actually very easy to understand. In the ammonia molecule, N and the three H atoms are connected by *** valence bonds; while the three H atoms have no valence bonds. Yes, you make a model yourself and use three bamboo sticks to connect three small hawthorns to an apple. Do you think it is more appropriate to call it a triangular pyramid or a tetrahedron? I hope you can understand. If you think it is right, just choose it as the best answer! hehe!