Check to see if any of these sentences are informal if they are correct them to be formal tenga cuidado con el yeso en su brazo
No puedes utilizar tu brazo a cocine
Para evite que le duela el brazo, tome el medicamento
mientras estás en casa, deja que tus padres te cuiden

tenga cuidado con el yeso en su brazo

No puedes utilizar tu brazo a cocine

are not formal

Explanation:

but the other 2 are because its telling you if you really are hurting take medicine and when your hurt your parents make you feel safe.

usualmente me lavo los dientes antes de acostarme pero ayer no me lavé.  

usualmente hago mis tareas a las 15: 00pm pero ayer las hice a las 20 pm.  

usualmente llego a mi casa a las siete pero ayer volví a las nueve  

usualmente cocino arroz pero ayer cociné fideos.  

usualmente llamo a mi hermano al mediodía pero ayer lo llamé en la noche

21. both telenovelas and soap operas are serial melodramatic genres in contrast, it's a rare event that a soap opera actor transitions well to into hollywood.22. the san sebastian international film festival- it is the only film festival in spain listed as a category “a” event, one of only 13 in the whole world.  the malaga film festival- the official name of the event is festival de málaga cine español (fmce) and began in 1998 to drive the spanish film industry.23. there are two main reasons for regional television in spain. the first is so that people can get the news in a timely fashion, the other is for entertainment.  24.the goya awards are just like the oscar basically. the goya awards are for the best spanish films of the years.25.she was the first woman to receive a chair at a spanish university and her home in la coruña, which belongs to the real academia galega, now houses the casa-museo pardo bazán, dedicated to the conservation and dissemination of the author's heritage