Masculine vs feminine adjectives when used with first person verbs

Question

I've been taking Spanish lessons through Duolingo and came across a question where a girl says "I sleep alone and eat alone." and you are asked to select the options for which is correct. It gave two answers that it says are correct:

• "Yo duermo sola y como sola." <-- I chose this one.
• "Yo duermo solo y como solo." <-- but this one was also listed as correct

Can either gender properly say either of those statements? Or should feminine/masculine speakers use their appropriate adjectives?

Answer 1

In spanish the 90% of adjectives has masculine and feminine gender. If you are a male, you have to choose the second option:

Yo duermo solo y como solo

If you are female you have to choose the first one:

Yo duermo sola y como sola

This is one of the most difficult things for foreigners, choose the right gender appropriately.

I'll try to give you a useful clue that will help you:

• Gender male: adjective normally ends with -e, -i, -o, -u (in singular) and -es, -is, -os and -us (in plural). In your case (assuming that you are a male, you have to choose one of this, solo to be exact)
• Female gender: adjective normally ended with -a (in singular) and -as (in plural).

If you want more information I can edit the post and give you some examples or expand some parts to give you more information.

Hope it helps!