1. Present Progressive:
narrates an action in progress uses the present tense of estar and the present participle of the main verb

2. bailar: bail + ando= bailando comer: com + iendo= comiendo
The present participle of regular –ar,-er, and –ir verbs is formed as follows:
bailar: bail + ando= bailando
comer: com + iendo= comiendo
aplaudir: aplaud + iendo= aplaudiendo

3. Stem-changing –ir verbs change their stem vowel in the present participle
Decir diciendo
Dormir durmiendo
Mentir mintiendo
Morir muriendo
Pedir pidiendo
Sentir sintiendo
Sugerir sugiriendo

4. Irregular present participles
Ir yendo (rarely used)
Poder pudiendo (rarely used)
Reír riendo
Sonreír sonriendo

5. When a stem of an –er or –ir verb ends in a vowel, the –i of the present participle is changed to a -y
Construir construyendo
Leer leyendo
Oír oyendo
Traer trayendo

6. Other verbs that use the present participle: express various shades of progression
Seguir: to keep doing something- Emilio sigue trabajando.: Emilio keeps working.
Ir: indicates a gradual or repeated process (more and more)- Cada día, voy amando a mi novia. I am loving my girlfriend more and more each day.
Venir: indicates a gradual action that accumulates or increases over time- Lo vengo estudiando desde la semana pasada. I have been studying it since last week.
Andar: conveys the idea of going around doing something or of always doing something.- Ramon anda diciendo mentiras: Ramon is going around telling lies.