gan > did

4 Out of the sea fair Titan's dewy face, 5 Up rose the gentle virgin from her place,

gentle > gentle; noble

6 And looked all about, if she might spy

if > [in the hope that]

7 Her beloved knight to move his manly pace:

to move > [moving]

8 For she had great doubt of his safety,

doubt of > fear for

9 Since late she saw him fall before his enemy.