Sentence:  Thus, for example, in the <WSD>line</WSD> of Quarte, the direct thrust is parried by dropping the point under the adversary's blade and circling upwards, throwing off the attack in the opposite <WSD>line</WSD> (that of Tierce), and upon the direct thrust in the <WSD>line</WSD> of Tierce, by a similar action throwing off the attack in the opposite <WSD>line</WSD> (that of Quarte). 
Meaning of the word marked with <WSD> tags:  The position in which the fencers hold their swords.