tongsis

In English, blends are usually formed from the first half of one word and the second half of another. For example:

• smog : smoke + fog
• motel : motor + hotel
• edutainment : education + entertainment

In contrast, in Malay blends tend to be the first half of two words, or sometimes three. For example:

• cerpen ('short story') : cerita + pendek
• tadika ('kindergarten') : taman + didik + kanak

However, I just learned one that seems to follow the English pattern, not the usual Malay pattern, though maybe it only exists in Indonesia:

• tongsis ('selfie stick') : tongkat + narsis (lit. 'a narcisist stick')

I wonder if this use of the second part of 'narsis' is influenced by the fact that this word comes from English? Or maybe Indonesian word formation works differently from that of Malay.

mengetahui

In Malay, nearly all roots are bisyllabic. There are a few exceptions; but monosyllabic roots tend to add an extra syllable when there is a prefix, empasising the bisyllabic expectation for roots. For example:

• cap ('stamp') becomes mengecap ('to stamp'), not *mencap
• cat ('paint') becomes pengecat ('painter'), not *pencat
• sah ('valid') becomes mengesahkan ('to confirm'), not *menyahkan

Note that baik ('good') and laut ('sea') are bisyllabic, so there is no need for this extra syllable:

• baik ('good') becomes membaiki ('to improve'), not *mengebaiki
• laut ('sea') becomes pelaut ('sailor'), not *pengelaut

However, I have no explanation why tahu ('to know') becomes mengetahui ('to know') rather than the expected *menahui. Why is the extra syllable added? Perhaps there is a feeling that tahu is monosyllabic, as the /h/ is weak (or sometimes omitted).