Complex sentence: During his time as dock engineer Foster completed only one dock Princes Dock he converted Manchester Basin to an enclosed dock Manchester Dock and expanded several other docks including George's Dock and Queen's Dock.
Split into simpler sentences: During his time as dock engineer, Foster completed only one dock (Princes Dock). He also converted Manchester Basin to an enclosed dock (Manchester Dock) and expanded several other docks including George's Dock and Queen's Dock.