Questions & Answers about Mereka membina rumah.
Mereka means they or them.
In Mereka membina rumah, it functions as the subject, so it means they.
A useful point: mereka is normally used for people, not for things or animals in standard Malay.
No. Malay pronouns do not usually mark gender.
So mereka can mean:
- they (mixed group)
- they (all male)
- they (all female)
The sentence gives no gender information unless the wider context tells you.