ok let's take examples
when we say that we must add 's' to the verb, if it is in the simple present tense and it is a third person singular. this is grammar
when we describe the changes that will happen to the verb love for example in different grammatical cases. this is analysis
in English there are only two cases for the verb in the present simple, either withe 's' or without. but in old languages such as Latin and Greek there are many cases, just like Arabic. for example if we take the verb أحب
it can be written - according to its position in these ways
أحب - يحب - تحب - يحبان - تحبان - يحبون - تحبون - نحب
and if follow this way for English we will say
I love - you love - he loves - she loves - it loves - they love - we love
and this is the traditional analysis, and it's impractical to use this way for English, because in English it's enough to say that it's with third person singular the simple tense verb takes 's' after it
because of that we call it traditional, not contemporary
because it does not work well with English, it's ok with the traditional languages like Latin and Greek