All my teachers had very good knowledge of their subject

[Nonverbis]

This excerpt is from Upstream Proficiency by Virginia Evans and Jenny Dooley.

All my teachers had very good knowledge of their subject, but their ability to konvey knowledge varied.

Please, have a look at the screenshot.

Could you tell me whether there is a typo here and it should be subjects?

 

[Rover_KE]

It should be "subjects".

"Please [no comma here] have a look at the screenshot."

Note how I've put the word you're asking about in quotation marks.

 

[Glizdka]

Could you tell me whether there is a typo?

I found it. ;-)

All my teachers had very good knowledge of their subject, but their ability to kconvey knowledge varied.

 

[5jj]

I can live with singular 'subject' in that sentence, provided that each teacher teaches only one subject.

 

[tedmc]

Convey knowledge is a strange collocation. Teach/impart knowledge?

 

[jutfrank]

It isn't a typo. It makes it clear that each teacher had just one subject.

 

[5jj]

Convey knowledge is a strange collocation.

I don't find it particularly strange. I found 28 examples in COCA.

 

[Glizdka]

It isn't a typo. It makes it clear that each teacher had just one subject.

I've always had a problem with that.

Does "Lions have tails" mean that each lion has mulriple tails?

Does "Lions have a tail" mean there's just one common tail each lion grows out of?

I just use common sense with these, and it works out for me.