Sorry to bother you all once again but i have another question i need some help with. My wife is actually Japanese but for some reason she struggles actually explaining the differences with some things.
はず と 確かに sound almost the same to me.
Please take a lot at these sentences.
To me, both of these sound exactly the same - to say (surely there is someone up there, there must be someone up there, it must be a big dog, im sure i said that etc.)
Please help me im pulling my hair out!
確かにもう言った
もう言ったはずです
確かに上にだれかいる
上にだれかいるはずです
確かに大きい犬です
大きい犬のはずです
Thank you
There is a pretty important difference between the 確かに and the はずです sentences. I'm not going to open a grammar book now so I'm going with how I feel about it. Let's take the first sentence (I'm going to change the はずです in はずだ to have homogeneous registry).
確かにもう言った tashika ni mou itta, "I definitely told you already"
もう言ったはずだ mou itta hazu da, "I'm sure I told you, don't you remember?", "I already told you once, don't make me repeat myself"
With the first sentence you are simply stating that you said something, and you are sure of it.
With the second sentence you have a slightly emotional, further meaning. The speaker is annoyed because he has to say something again. Depending on the intonation, this sentence could express severe annoyance or even anger.
The focus on the 確かに sentence is the fact that you did say it. On the second one, it's the fact that you are annoyed that your interlocutor is forgetful or is not listening. Often you can barely perceive this,
if said in a very calm way it's just a normal way of reminding something to someone.
Take away the もう:
言ったはずだ itta hazu da
Then the expression has become
quite strong. Even with です:
言ったはずです itta hazu desu
The annoyance has become patent. Okay next one. The translations are inaccurate, I am just trying to emphasize and manifest their potential meaning.
確かに上にだれかいる tashikani ue ni dareka iru, "I heard someone walking upstairs"
上にだれかいるはずだ ue ni dareka iru hazu da, "there got to be someone upstairs"
Again I like it with だ. :emoji_grinning: This is slightly different now. The 確かに is similar to the 言った example. If I just read it, what I imagine is a man standing at the ground floor of a house, maybe a detective, and he just heard someone walking on the floor above; or maybe he saw someone behind the window from outside the house. It does sound a little creepy I have to say.
With the はずだ sentence, you are making a conjecture. You have enough evidence to state that there is someone on the floor above. Maybe you just got in and the stove is on; there is nobody on the ground floor: there must be someone on the floor above then.
Another meaning could be: you WANT someone to be 上に, maybe because you need someone's assistance. Even if you don't have enough proof, you know it's very likely that at this time of the day someone would be upstairs. A possible translation would be: "there has to be someone upstairs".
Okay another one is: Rick went upstairs to check, came back and said that there was no one. Now you are annoyed because you know there
should be someone upstairs, so you are telling Rick 誰かいるはずだ dareka iru hazu da, "there must be someone, go back and check again", or "I'm going to check, you are useless". It doesn't mean you are sure of that, you are just annoyed that Rick came back without finding anyone.
確かに大きい犬です tashikani ookii inu desu, "yep, I can see it's a large dog!"
大きい犬のはずです ookii inu no hazu desu, "I've been told it's a large dog"
The 確かに sentence is very easy indeed.

: In this case my impression is that the person who is uttering the sentence is actually looking at the dog as he speaks. He can see that the dog is large. Again, with 確かに you have certainty.
If the person is not looking at the dog, then the person definitely saw the dog in the past. He/she is saying "it definitely was a large dog". It's obviously not mandatory, but another way of saying it would be 確かに大きい犬でした tashika ni ookii inu deshita, in the past form.
はずです here indicates that maybe you heard from Rick that the dog is large, and you are telling Mary what you heard. The sentence expresses a feeling of urgency or necessity. "There should be a large dog" could be a possible translation in this case.
Hope this helps.