Three Oral words in Malay

There are three oral words in Malay that I know of. They are cuma, kalau and jadi. These three words are usually used orally. Now look at the written words for them as listed below.

1 The written word for cuma is hanya. In Malay, both are translated as "only".
a) "Saya cuma bergurau sahaja," kata Ali kepada saya. ["I was just joking only," said Ali to me.]
b) Saya hanya datang ke sini sekali-sekala. [I only come here once in a while.]

2 The written word for kalau is jika, jikalau, sekiranya and seandainya all of which mean "if".
a) "Kalau awak ada masa lapang, datanglah ke rumahku," kata Zamri. ["If you are free come to my house," said Zamri.]
b) Jika kita rajin belajar, kita pasti akan lulus dalam peperiksaan. [If we study hard, we certailny will pass in the exams.]

3 The written word for jadi is oleh itu. In English, it is the equivalent of "so".
a) "Jadi, kau mesti belajar bersungguh-sungguh," kata Muthu. ["So you must work hard," said Muthu.
b) Oleh itu, kita mestilah menjaga kebersihan di sekitar kita. [So we must maintain the cleanliness of our surroundings.]