Well, today I'm going to share some sentences and words in Japanese which I found in the web yesterday. So here it is!
Yes-- hai
no -- iie
it`s ok  -- sou desu
please -- douzo
thanks-- arigatou
 thanks a lot-- doumo arigatou gozaimasu
you are welcome -- douitashimashite
sorry -- gomen nasai
excuse me -- sumimasen
good morning-- o hayou gozaimasu
good afternoon-- konbanwa
Hi, have a good day -- konnichiwa
good night -- o yasumi nasai
Bye-- sayounara
I understand-- wakari mashita
I don't understand-- wakari masen
Can you help me? -- onegai shimasu