How do I get high marks for language analysis?

The key to scoring well on attention and sensitivity towards a writer's linguistic techniques and effects is to identify the technique, explain its effect, and then tie this into your overarching answer to the main question. It is crucial that all three of these steps are taken, otherwise candidates may be denied high marks in this area.

For example, for a question such as, 'In I wandered lonely as a cloud, how does Wordsworth convey his excitement at his discovery of daffodils?', you might want to begin by looking at the first verse. A technique you might identify would be the poet's personification of the daffodils with words such as 'crowd' and 'dancing'. Then, you could argue that the effect of this is to make the poet's and our own relationship with these flowers more intimate by encouraging us to recognise in them our own human characteristics. Lastly, in anwering the main question, you could suggest that this technique emphasises the poet's excitement because the lively crowd of daffodils which he comes across contrasts with his initial "lonely" wandering, thus creating a sudden sense of shared companionship with nature.