It's the weak chink in most people's armour, if they were born after 1975. Some folk made the point that while my last post about the Pattern of Mistakes marking pro-forma was an excellent one, it assumed that most teachers could spot a grammar error. One colleague (or co-worker, depending on your confidence with the -eague ending) said gaily, 'I just draw a wiggly line under it and write 'Watch your expression' if it sounds wrong. Bless her. She reads Jodi Picoult in the holidays.
Anyway, to remediate this I have made a checklist of grammar terms that you should know for Stage 4 and 5 English. I prefer Swan's Practical English Usage because I'm old and exhaustive. But NESA like Beverly Derewianka's book. Either one is probably fine, but you've got to know all the things on the checklist - and it's not a bad idea to teach them explicitly.
Have a lovely week, with or without wiggly lines.