Content QA and grammar questions
Grammar questions interviewers ask directly, with short rule-based answers.
'It's' is 'it is' or 'it has'. 'Its' is possessive. Test by expanding to 'it is'; if the sentence breaks, use 'its'.
'Affect' is usually the verb (to influence); 'effect' is usually the noun (the result). 'The change affected sales' and 'the effect on sales'.
Between two complete sentences that are closely related, or to separate list items that contain commas. If either side cannot stand alone as a sentence, use a comma or a dash instead.
'Fewer' for things you count (fewer errors), 'less' for things you measure (less time).
'Who' is the subject, 'whom' the object. Substitute 'he/him': if 'him' fits, use 'whom'.
Make a short list of the document's own choices (spellings, capitals, number formats, headings) on the first pass, then check every later instance against the list. Search-and-find handles most of it.
Practise out loud. Say each answer once as written, then again in your own words with your own number or story.
Have a number ready. "My Proofreading score is at benchmark on a timed test" is a stronger answer than "I am good at it". Take the test and quote the result.
More in Office and BPO