<span style="color:rgb(20,20,20);background-color:rgb(252,252,255);">I</span><span style="color:rgb(20,20,20);background-color:rgb(252,252,255);"> saw these sentences which are unusual conditionals.</span><br style="color:rgb(20,20,20);"/><br style="color:rgb(20,20,20);"/><span style="color:rgb(20,20,20);background-color:rgb(252,252,255);">1. If it was yesterday, I will have bought the car. - sounds like a condition but will have sounds off </span><br style="color:rgb(20,20,20);"/><br style="color:rgb(20,20,20);"/><span style="color:rgb(20,20,20);background-color:rgb(252,252,255);">2. If it was yesterday, I must have bought the car. - sounds like a dream or someone unsure of what's happening </span><br style="color:rgb(20,20,20);"/><br style="color:rgb(20,20,20);"/><span style="color:rgb(20,20,20);background-color:rgb(252,252,255);">3. If it was yesterday, I bought the car. - sounds a bit weird </span><br style="color:rgb(20,20,20);"/><br style="color:rgb(20,20,20);"/><span style="color:rgb(20,20,20);background-color:rgb(252,252,255);">From the thread below, I am just not sure if they are grammatically correct.</span><br style="color:rgb(20,20,20);"/><br style="color:rgb(20,20,20);"/><span style="color:rgb(20,20,20);background-color:rgb(252,252,255);">Also, when are they used?</span><br style="color:rgb(20,20,20);"/><br style="color:rgb(20,20,20);"/><p><span style="color:rgb(20,20,20);background-color:rgb(252,252,255);">Thanks </span></p><p><a href='https://english.stackexchange.com/questions/176825/2nd-condition-or-mixing-2nd-and-3rd-for-assumption-time-in-the-past' target='_blank' rel='nofollow'>https://english.stackexchange.com/questions/176825/2nd-condition-or-mixing-2nd-and-3rd-for-assumption-time-in-the-past</a><br/></p>