Hi Vincent, How do I explain this sentence is incorrect to my teacher? Is my last comment not adequate for your needs? We can't use "equals" instead of "is". Why not? I just said that 'is' is more common. HOw do I explain? I need to tell them the reasons.
Take away three from twenty-eight equals twenty-five.
a) Take away three from twenty-eight equals twenty-five.
"Take away three from twenty-eight" is a singular subject, so the verb "equals" is correct. What do you think? It's correct as my friend say? "singular subject"?