Using そんなに and それほど Shouldn’t Be Complicated
I’d say some learners got confused with a nuance of そんなに and それほど. But, don’t worry about it. You would figure out the nuance of them, after reading this. Let me introduce the way to correctly use them!
そんなに / それほど (sonnani/sorehodo)
“そんなに and それほど” mean “That (much)” and the difference between them is that basically “そんなに” has been used as subjective opinions. Whereas, “それほど” has been used as objective opinions. For instance, “このペンはそんなに高くない。(This pen is not that expensive (for me).)” which pen might be expensive for others. Whereas “このペンはそれほど高くない(This pen is not that expensive (for everyone).)” which pen might not be expensive for others. That’s the difference between them. However, some native speakers use them as the same meaning and in this case, “そんなに” is used in daily conversations as casual than “それほど”.