"I do not run in the summer."

Translation: Eu não corro no verão.

[PetoG]

So, months do not use articles (em janeiro), but seasons do (no verão)? Did I deduce this correctly?

[Paulenrique]

Exacty. Sidenote: if you give a description for a month, then do not use article. "Verão é estação mais quente".

[Kaoriocha]

Why not "eu não corro em verão"? Which words are there mean on/in/at? I remember that we studied "na"=on, so is it "on" = "na" (fem) & "no" (mas)?

[r_i_l_e_y]

"em" = in / at / on

"no" = "em" + "o" (in the / at the / on the) (masc)

"na" = "em" + "a" (in the / at the / on the) (fem)

[jenlawson]

It is so helpful to see it broken down this way. Thank you.

[Paulenrique]

And some preposition+article are optional, others mandatory. In this case you have to link. Plural forms: nos and nas

[IsraelRoch5]

Why not "Eu não corro durante o verão." ?

[Naasei]

I always forget em + o = no so I wrote em o.

Shouldn't that be accepted though, if one chooses not to use the contraction, just as in English one can wrie can't or cannot

[Paulenrique]

Some contractions are mandatory, such as "em + o".

[Naasei]

Thanks