Halo RSagum, "Kalau" dan "jika" sama-sama bisa digunakan secara formal, tergantung kalimat dan konteksnya. Namun saya sendiri lebih suka menggunakan "jika" dalam tulisan formal. =) Esther

Hello, I am cynthia, I saw your brief details and decided to write you. I want to make a good friendship.I Feel we shall make a better introduction in our next communication. contact me through my email address ([email protected] ) for more details and my pictures. I will like to know you better for more personal information, please do not write me on this site because i do not visit the site all the time..kindly reply me with ([email protected] )i am waiting . Thanks

better is JIKA..

jika...

"kalau" dan "jika" sama pengertiannya. Tapi dalam bahasa baku Indonesia, "jika" lebih banyak digunakan karena terkesan lebih formal :)