You may well want to alter sentence ordering. The translator may have used three sentences where the original had only one. You can also merge paragraphs.
adjusting by dragging with the mouse
To merge sentences or paragraphs, simply grab and drag it up to the next one above in the same language. Or use the Join button. Or press F4.
To split a sentence or paragraph, choose the Split button or press Ctrl+F4.
Finally you will want to save (Ctrl+F2) the results.
See also: Aligner contents