i'm a little confused over this one. if anyone could explain, that'd be great...
i though that 'tolong' more or less translated as 'please, help me by ...' and that 'mohon' translated as 'please, i beseech or beg you to ...'
but in this example i'm not sure how to understand the intent...
'please help me by drinking water' or 'please, i beg you to drink some water'.
but also, for example, if you were offering someone water, could you say: 'silakan minum air', ie 'please drink some of this water'?
"Tolong" is used in wider contexts. It's not just "help me by doing". For example,
-- "Tolong jangan memganggu saya.": Please don't disturb me.
-- "Tolong buka pintunya.": Please open the door.
-- "Tolong jangan pergi.": Please don't go.
-- "Tolong masuk.": Please come in.
These sentences are provided by Indonesian native speakers. If you accept/obey the speaker's request/command, it would be beneficial for the speaker.
"Silakan" is sometimes mixed up with "tolong". Here are typical situations in use.
-- "Silakan minum air.": Please drink water. Help yourself. (i.e. The speaker is offering you)
-- "Tolong minum air.": Please drink water, otherwise you shall die. (i.e. The speaker is asking a patient to drink, for example)
-- "Silakan masuk.": Welcome to our house (or somewhere). Please come in.
-- "Tolong masuk.": Please come in, and clean my room. (i.e. The speaker is inside his room, and asking his housekeeper to enter. You can also say "Masuk!" but it sounds too bossy. So, add "tolong" to be polite.)