Comparatives and superlatives are ways to compare different items. Comparatives are when there is a comparison of two items while superlatives compare three or more items.
Alright, now we are talking comparatives and superlatives and I think it may sound like a pretty basic idea here. Generally, what you're going to do is, sometimes you're going to put adjectives or modifiers into a comparative form, sometimes you're going to put them into a superlative form. You're going to use the comparative form when you're comparing just two things and the regular form of that comparative is to add -er to the end, like the word 'smarter', alright? Some words that require less or more rather than the -er like, 'less intelligent'. So those are some of the regular forms. And then sometimes we have some irregular forms of the comparative; least, most, better, worse. So you've got to work those in where the words are necessitated. Now, if you were comparing three or more things, you've got to move to the superlative form. And the regular form of the superlative is to add -est to the end, so instead of smarter, smartest; instead of less intelligent, least intelligent. And those irregular forms shift as well, to least, most, worst and best. So that's really basic and sometimes it seems a little bit intuitive but there can be times where we get caught up on these, so let's take a look at some examples. Here in this sentence we've got 'Rachel is a better student than her brother; she goofs off less and studies more'. Now, everything looks good here. The first thing I'm going to do to make sure I'm okay is to check how many things are compared. So I've got Rachel and I've got her brother; I've got two things which means this should be in the comparative form. So, we have better with that -er on the end, we're good there and then we've got less and more, we are good there. The next example, if we wanted to take this to the superlative form we'd say 'Rachel is the best student in her family; she goofs off the least and studies the most'. So now we're looking at how many people are being compared; we've Rachel, but when we compare it to a group, her family; we're no longer at two, we're at more than two. So we've got to go to the superlative form and we're good here because we have 'best' and then we've moved this to least and most. So that's how it works in the basics. Let's take a look at some filling the blank spaces; 'Of all the people in the classroom, the teacher is by far the older or the oldest?' Let's take a look, so we've got the things being compared; the teacher and that teacher is being compared to all the people in the classroom. We know that that's more than two people so we've got to fill this in with the superlative. It should be, by far the 'oldest'. This one; and I think this is the easiest one to make a mistake on; it's the 'tallest' or 'taller' of the three buildings. I'm kind of inclined to say 'taller' but when I look at this I see that I've got three buildings that are being compared, now three is definitely more than two which means I've got to go superlative and I've got to say; 'It's the tallest building out of the three'. So, basically to remember your comparative and superlatives, the big trick is to check your numbers. Always go back, figure out how many things are being compared and then from there you can make the best decision.