Meaning trap
get through to
make someone understand
to succeed in making someone understand what you are trying to say, especially when it is difficult.

Don't mix these meanings
Same phrase, different job.
to succeed in making someone understand what you are trying to say, especially when it is difficult.
Another meaning of 'get through to' is 'make contact by phone'; compare the examples to keep the meanings separate.
Hear it in context
Notice where the phrase sounds natural.
No matter how many times I explain, I just can't get through to him.
In group projects, it's important to get through to your teammates so everyone understands their role.
Fix the pattern
One small grammar move makes it sound right.
Not: It's hard to get through them this idea.
Say: It's hard to get through to them. / get this idea through to them.
Use 'get through TO' someone; the idea goes 'through to them'.
Which sounds natural?
Tap the one a native speaker would say.
'Get through to someone' (make them understand) is natural; 'make him comprehend the seriousness' is stiff.
Build natural chunks
Words that usually travel with it.
get through to + person
- to them
- to students
- the message
- somehow
Don't confuse it
Related
Other meanings and phrases to compare.
- get through to (make contact by phone) — Another meaning of 'get through to' is 'make contact by phone'; compare the examples to keep the meanings separate.