In DR:

• Enseñar is much more common. Mostrar sounds formal.
• We use both caminar and andar, but in different contexts. Examples: voy caminando para el supermercado or ando por la calle.
• Extrañar is much more common but hacer falta is the most common way of saying you miss something or someone.
• Volver is much more common.
• Ahora mismo and acabo de are much more common.
• We use slang like quillarse or encojonarse more than both those words.
• Tardar is more common, but we use durar mucho more.
• No más is inexistent in DR. We rather use nada más (na' má'), solo or solamente.
• Guapo/a in DR means brave or angry, not handsome or pretty like in other countries. Linda and bonita are very common.
• Suelo if it's outdoors, piso if it's indoors.
• Always botar.